21272397903 has 32 divisors (see below), whose sum is σ = 32488012800. Its totient is φ = 13750181568.

The previous prime is 21272397877. The next prime is 21272397907. The reversal of 21272397903 is 30979327212.

It is a happy number.

It is not a de Polignac number, because 21272397903 - 2⁵ = 21272397871 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21272397907) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24826 + ... + 207752.

It is an arithmetic number, because the mean of its divisors is an integer number (1015250400).

Almost surely, 2^21272397903 is an apocalyptic number.

21272397903 is a deficient number, since it is larger than the sum of its proper divisors (11215614897).

21272397903 is a wasteful number, since it uses less digits than its factorization.

21272397903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183068 (or 183062 counting only the distinct ones).

The product of its (nonzero) digits is 285768, while the sum is 45.

The spelling of 21272397903 in words is "twenty-one billion, two hundred seventy-two million, three hundred ninety-seven thousand, nine hundred three".