21273210772 has 24 divisors (see below), whose sum is σ = 40794630912. Its totient is φ = 9626275200.

The previous prime is 21273210769. The next prime is 21273210809. The reversal of 21273210772 is 27701237212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1074229 + ... + 1093852.

It is an arithmetic number, because the mean of its divisors is an integer number (1699776288).

Almost surely, 2^21273210772 is an apocalyptic number.

21273210772 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21273210772 is a deficient number, since it is larger than the sum of its proper divisors (19521420140).

21273210772 is a wasteful number, since it uses less digits than its factorization.

21273210772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2168319 (or 2168317 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 34.

Adding to 21273210772 its reverse (27701237212), we get a palindrome (48974447984).

The spelling of 21273210772 in words is "twenty-one billion, two hundred seventy-three million, two hundred ten thousand, seven hundred seventy-two".