39955942656 has 576 divisors, whose sum is σ = 147686031360. Its totient is φ = 10391224320.

The previous prime is 39955942643. The next prime is 39955942699. The reversal of 39955942656 is 65624955993.

39955942656 is a `hidden beast` number, since 3 + 9 + 9 + 559 + 4 + 26 + 56 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 39955942593 and 39955942602.

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, 25497585 + ... + 25499151.

It is an arithmetic number, because the mean of its divisors is an integer number (256399360).

Almost surely, 2^39955942656 is an apocalyptic number.

39955942656 is a gapful number since it is divisible by the number (36) 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 39955942656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73843015680).

39955942656 is an abundant number, since it is smaller than the sum of its proper divisors (107730088704).

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

39955942656 is a wasteful number, since it uses less digits than its factorization.

39955942656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1647 (or 1627 counting only the distinct ones).

The product of its digits is 78732000, while the sum is 63.

The spelling of 39955942656 in words is "thirty-nine billion, nine hundred fifty-five million, nine hundred forty-two thousand, six hundred fifty-six".