21262775764 has 12 divisors (see below), whose sum is σ = 37217994688. Its totient is φ = 10629063000.

The previous prime is 21262775731. The next prime is 21262775861. The reversal of 21262775764 is 46757726212.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 560562 + ... + 597289.

Almost surely, 2^21262775764 is an apocalyptic number.

It is an amenable number.

21262775764 is a deficient number, since it is larger than the sum of its proper divisors (15955218924).

21262775764 is a wasteful number, since it uses less digits than its factorization.

21262775764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1162446 (or 1162444 counting only the distinct ones).

The product of its digits is 1975680, while the sum is 49.

The spelling of 21262775764 in words is "twenty-one billion, two hundred sixty-two million, seven hundred seventy-five thousand, seven hundred sixty-four".