21952971663 has 16 divisors (see below), whose sum is σ = 33456327936. Its totient is φ = 12542987520.

The previous prime is 21952971559. The next prime is 21952971707. The reversal of 21952971663 is 36617925912.

It is not a de Polignac number, because 21952971663 - 2¹⁰ = 21952970639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21952971863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118783 + ... + 240863.

It is an arithmetic number, because the mean of its divisors is an integer number (2091020496).

Almost surely, 2^21952971663 is an apocalyptic number.

21952971663 is a deficient number, since it is larger than the sum of its proper divisors (11503356273).

21952971663 is a wasteful number, since it uses less digits than its factorization.

21952971663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130654.

The product of its digits is 1224720, while the sum is 51.

It can be divided in two parts, 219529 and 71663, that added together give a palindrome (291192).

The spelling of 21952971663 in words is "twenty-one billion, nine hundred fifty-two million, nine hundred seventy-one thousand, six hundred sixty-three".