23161621456621 has 4 divisors (see below), whose sum is σ = 23374113396700. Its totient is φ = 22949129516544.

The previous prime is 23161621456613. The next prime is 23161621456639. The reversal of 23161621456621 is 12665412616132.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19460326440996 + 3701295015625 = 4411386^2 + 1923875^2 .

It is a cyclic number.

It is not a de Polignac number, because 23161621456621 - 2³ = 23161621456613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23161621456321) 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, 106245969876 + ... + 106245970093.

It is an arithmetic number, because the mean of its divisors is an integer number (5843528349175).

Almost surely, 2^{23161621456621} is an apocalyptic number.

It is an amenable number.

23161621456621 is a deficient number, since it is larger than the sum of its proper divisors (212491940079).

23161621456621 is a wasteful number, since it uses less digits than its factorization.

23161621456621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212491940078.

The product of its digits is 622080, while the sum is 46.

The spelling of 23161621456621 in words is "twenty-three trillion, one hundred sixty-one billion, six hundred twenty-one million, four hundred fifty-six thousand, six hundred twenty-one".