981655878840 has 256 divisors, whose sum is σ = 3638060697600. Its totient is φ = 206348027904.

The previous prime is 981655878817. The next prime is 981655878877. The reversal of 981655878840 is 48878556189.

It is a super-2 number, since 2×981655878840² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2770389 + ... + 3104571.

It is an arithmetic number, because the mean of its divisors is an integer number (14211174600).

Almost surely, 2^981655878840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 981655878840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1819030348800).

981655878840 is an abundant number, since it is smaller than the sum of its proper divisors (2656404818760).

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

981655878840 is a wasteful number, since it uses less digits than its factorization.

981655878840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334486 (or 334482 counting only the distinct ones).

The product of its (nonzero) digits is 154828800, while the sum is 69.

The spelling of 981655878840 in words is "nine hundred eighty-one billion, six hundred fifty-five million, eight hundred seventy-eight thousand, eight hundred forty".