123611622561 has 32 divisors (see below), whose sum is σ = 209327513600. Its totient is φ = 70622390160.

The previous prime is 123611622539. The next prime is 123611622569. The reversal of 123611622561 is 165226116321.

123611622561 is a `hidden beast` number, since 1 + 2 + 3 + 61 + 16 + 22 + 561 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-123611622561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123611622569) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1038030 + ... + 1150968.

It is an arithmetic number, because the mean of its divisors is an integer number (6541484800).

Almost surely, 2^123611622561 is an apocalyptic number.

It is an amenable number.

123611622561 is a deficient number, since it is larger than the sum of its proper divisors (85715891039).

123611622561 is a wasteful number, since it uses less digits than its factorization.

123611622561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118746 (or 118740 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

Adding to 123611622561 its reverse (165226116321), we get a palindrome (288837738882).

The spelling of 123611622561 in words is "one hundred twenty-three billion, six hundred eleven million, six hundred twenty-two thousand, five hundred sixty-one".