21263646164 has 24 divisors (see below), whose sum is σ = 37694995968. Its totient is φ = 10493887680.

The previous prime is 21263646161. The next prime is 21263646167. The reversal of 21263646164 is 46164636212.

It is an interprime number because it is at equal distance from previous prime (21263646161) and next prime (21263646167).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21263646161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 331424 + ... + 390344.

It is an arithmetic number, because the mean of its divisors is an integer number (1570624832).

Almost surely, 2^21263646164 is an apocalyptic number.

It is an amenable number.

21263646164 is a deficient number, since it is larger than the sum of its proper divisors (16431349804).

21263646164 is a wasteful number, since it uses less digits than its factorization.

21263646164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60095 (or 60093 counting only the distinct ones).

The product of its digits is 248832, while the sum is 41.

The spelling of 21263646164 in words is "twenty-one billion, two hundred sixty-three million, six hundred forty-six thousand, one hundred sixty-four".