21326011623 has 24 divisors (see below), whose sum is σ = 35923316000. Its totient is φ = 12186290592.

The previous prime is 21326011621. The next prime is 21326011639. The reversal of 21326011623 is 32611062312.

21326011623 is a `hidden beast` number, since 2 + 1 + 3 + 26 + 0 + 11 + 623 = 666.

It is not a de Polignac number, because 21326011623 - 2¹ = 21326011621 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 (21326011621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3451078 + ... + 3457251.

Almost surely, 2^21326011623 is an apocalyptic number.

21326011623 is a deficient number, since it is larger than the sum of its proper divisors (14597304377).

21326011623 is an equidigital number, since it uses as much as digits as its factorization.

21326011623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6908356 (or 6908339 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

Adding to 21326011623 its reverse (32611062312), we get a palindrome (53937073935).

The spelling of 21326011623 in words is "twenty-one billion, three hundred twenty-six million, eleven thousand, six hundred twenty-three".