1642861440 has 640 divisors, whose sum is σ = 6646907520. Its totient is φ = 383201280.

The previous prime is 1642861439. The next prime is 1642861447. The reversal of 1642861440 is 441682461.

It is a happy number.

1642861440 is a `hidden beast` number, since 1 + 642 + 8 + 6 + 1 + 4 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a super-3 number, since 3×1642861440³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1642861395 and 1642861404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1642861447) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 24520287 + ... + 24520353.

It is an arithmetic number, because the mean of its divisors is an integer number (10385793).

Almost surely, 2^1642861440 is an apocalyptic number.

1642861440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1642861440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3323453760).

1642861440 is an abundant number, since it is smaller than the sum of its proper divisors (5004046080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1642861440 is a wasteful number, since it uses less digits than its factorization.

1642861440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 1642861440 is about 40532.2271778890. The cubic root of 1642861440 is about 1179.9591674083.

The spelling of 1642861440 in words is "one billion, six hundred forty-two million, eight hundred sixty-one thousand, four hundred forty".