23154402621561 has 4 divisors (see below), whose sum is σ = 30872536828752. Its totient is φ = 15436268414372.

The previous prime is 23154402621551. The next prime is 23154402621577. The reversal of 23154402621561 is 16512620445132.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 23154402621561 - 2²⁹ = 23153865750649 is a prime.

It is a super-2 number, since 2×23154402621561² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (23154402621551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3859067103591 + ... + 3859067103596.

It is an arithmetic number, because the mean of its divisors is an integer number (7718134207188).

Almost surely, 2^{23154402621561} is an apocalyptic number.

It is an amenable number.

23154402621561 is a deficient number, since it is larger than the sum of its proper divisors (7718134207191).

23154402621561 is an equidigital number, since it uses as much as digits as its factorization.

23154402621561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7718134207190.

The product of its (nonzero) digits is 345600, while the sum is 42.

The spelling of 23154402621561 in words is "twenty-three trillion, one hundred fifty-four billion, four hundred two million, six hundred twenty-one thousand, five hundred sixty-one".