15561955008 has 112 divisors (see below), whose sum is σ = 46154705760. Its totient is φ = 5141348352.

The previous prime is 15561955001. The next prime is 15561955009. The reversal of 15561955008 is 80055916551.

15561955008 is a `hidden beast` number, since 1 + 5 + 56 + 1 + 95 + 500 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (15561955001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 155416 + ... + 235112.

Almost surely, 2^15561955008 is an apocalyptic number.

15561955008 is a gapful number since it is divisible by the number (18) 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 15561955008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23077352880).

15561955008 is an abundant number, since it is smaller than the sum of its proper divisors (30592750752).

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

15561955008 is a wasteful number, since it uses less digits than its factorization.

15561955008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79831 (or 79815 counting only the distinct ones).

The product of its (nonzero) digits is 270000, while the sum is 45.

The spelling of 15561955008 in words is "fifteen billion, five hundred sixty-one million, nine hundred fifty-five thousand, eight".