623563215561 has 144 divisors (see below), whose sum is σ = 1086612246720. Its totient is φ = 341499525120.

The previous prime is 623563215553. The next prime is 623563215577. The reversal of 623563215561 is 165512365326.

623563215561 is a `hidden beast` number, since 6 + 2 + 3 + 5 + 63 + 21 + 5 + 561 = 666.

It is not a de Polignac number, because 623563215561 - 2³ = 623563215553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (623563215161) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 169767621 + ... + 169771293.

It is an arithmetic number, because the mean of its divisors is an integer number (7545918380).

Almost surely, 2^623563215561 is an apocalyptic number.

It is an amenable number.

623563215561 is a deficient number, since it is larger than the sum of its proper divisors (463049031159).

623563215561 is a wasteful number, since it uses less digits than its factorization.

623563215561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3928 (or 3912 counting only the distinct ones).

The product of its digits is 972000, while the sum is 45.

The spelling of 623563215561 in words is "six hundred twenty-three billion, five hundred sixty-three million, two hundred fifteen thousand, five hundred sixty-one".