1871216640 has 384 divisors, whose sum is σ = 6870165120. Its totient is φ = 488374272.

The previous prime is 1871216629. The next prime is 1871216647. The reversal of 1871216640 is 466121781.

It is a happy number.

1871216640 is a `hidden beast` number, since 1 + 8 + 7 + 1 + 2 + 1 + 6 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

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 = 1871216595 and 1871216604.

It is not an unprimeable number, because it can be changed into a prime (1871216647) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 39813097 + ... + 39813143.

It is an arithmetic number, because the mean of its divisors is an integer number (17891055).

Almost surely, 2^1871216640 is an apocalyptic number.

1871216640 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 1871216640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3435082560).

1871216640 is an abundant number, since it is smaller than the sum of its proper divisors (4998948480).

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

1871216640 is an frugal number, since it uses more digits than its factorization.

1871216640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 1871216640 is about 43257.5616511148. The cubic root of 1871216640 is about 1232.2760948654.

The spelling of 1871216640 in words is "one billion, eight hundred seventy-one million, two hundred sixteen thousand, six hundred forty".