21249874953 has 48 divisors (see below), whose sum is σ = 32313206016. Its totient is φ = 13442215680.

The previous prime is 21249874951. The next prime is 21249874957. The reversal of 21249874953 is 35947894212.

It is not a de Polignac number, because 21249874953 - 2¹ = 21249874951 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21249874953.

It is not an unprimeable number, because it can be changed into a prime (21249874951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2823151 + ... + 2830667.

It is an arithmetic number, because the mean of its divisors is an integer number (673191792).

Almost surely, 2^21249874953 is an apocalyptic number.

It is an amenable number.

21249874953 is a deficient number, since it is larger than the sum of its proper divisors (11063331063).

21249874953 is a wasteful number, since it uses less digits than its factorization.

21249874953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7774 (or 7771 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 54.

The spelling of 21249874953 in words is "twenty-one billion, two hundred forty-nine million, eight hundred seventy-four thousand, nine hundred fifty-three".