15561187660 has 36 divisors (see below), whose sum is σ = 34713845712. Its totient is φ = 5858327296.

The previous prime is 15561187651. The next prime is 15561187679. The reversal of 15561187660 is 6678116551.

15561187660 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×15561187660² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 15561187660.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1340344 + ... + 1351903.

It is an arithmetic number, because the mean of its divisors is an integer number (964273492).

Almost surely, 2^15561187660 is an apocalyptic number.

15561187660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15561187660 is an abundant number, since it is smaller than the sum of its proper divisors (19152658052).

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

15561187660 is a wasteful number, since it uses less digits than its factorization.

15561187660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2692290 (or 2692271 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 46.

The spelling of 15561187660 in words is "fifteen billion, five hundred sixty-one million, one hundred eighty-seven thousand, six hundred sixty".