1645884240 has 960 divisors, whose sum is σ = 7528660992. Its totient is φ = 287539200.

The previous prime is 1645884221. The next prime is 1645884259. The reversal of 1645884240 is 424885461.

It is an interprime number because it is at equal distance from previous prime (1645884221) and next prime (1645884259).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1645884192 and 1645884201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 53093025 + ... + 53093055.

Almost surely, 2^1645884240 is an apocalyptic number.

1645884240 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 1645884240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3764330496).

1645884240 is an abundant number, since it is smaller than the sum of its proper divisors (5882776752).

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

1645884240 is a wasteful number, since it uses less digits than its factorization.

1645884240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 42.

The square root of 1645884240 is about 40569.4988877112. The cubic root of 1645884240 is about 1180.6824167218.

The spelling of 1645884240 in words is "one billion, six hundred forty-five million, eight hundred eighty-four thousand, two hundred forty".