15561368222550 has 48 divisors (see below), whose sum is σ = 38628567001872. Its totient is φ = 4145787030400.

The previous prime is 15561368222539. The next prime is 15561368222563. The reversal of 15561368222550 is 5522286316551.

It is a junction number, because it is equal to n+sod(n) for n = 15561368222493 and 15561368222502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 48729849 + ... + 49048148.

It is an arithmetic number, because the mean of its divisors is an integer number (804761812539).

Almost surely, 2^{15561368222550} is an apocalyptic number.

15561368222550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

15561368222550 is an abundant number, since it is smaller than the sum of its proper divisors (23067198779322).

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

15561368222550 is a wasteful number, since it uses less digits than its factorization.

15561368222550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97779073 (or 97779068 counting only the distinct ones).

The product of its (nonzero) digits is 4320000, while the sum is 51.

The spelling of 15561368222550 in words is "fifteen trillion, five hundred sixty-one billion, three hundred sixty-eight million, two hundred twenty-two thousand, five hundred fifty".