21123633232664 has 32 divisors (see below), whose sum is σ = 39662444642400. Its totient is φ = 10546985729280.

The previous prime is 21123633232649. The next prime is 21123633232687. The reversal of 21123633232664 is 46623233632112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38605634 + ... + 39148974.

It is an arithmetic number, because the mean of its divisors is an integer number (1239451395075).

Almost surely, 2^{21123633232664} is an apocalyptic number.

It is an amenable number.

21123633232664 is a deficient number, since it is larger than the sum of its proper divisors (18538811409736).

21123633232664 is a wasteful number, since it uses less digits than its factorization.

21123633232664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 550163 (or 550159 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 44.

Adding to 21123633232664 its reverse (46623233632112), we get a palindrome (67746866864776).

The spelling of 21123633232664 in words is "twenty-one trillion, one hundred twenty-three billion, six hundred thirty-three million, two hundred thirty-two thousand, six hundred sixty-four".