21504334975 has 48 divisors (see below), whose sum is σ = 28491676416. Its totient is φ = 16072704000.

The previous prime is 21504334967. The next prime is 21504334979. The reversal of 21504334975 is 57943340512.

It is not a de Polignac number, because 21504334975 - 2³ = 21504334967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21504334979) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3078687 + ... + 3085663.

It is an arithmetic number, because the mean of its divisors is an integer number (593576592).

Almost surely, 2^21504334975 is an apocalyptic number.

21504334975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21504334975 is a deficient number, since it is larger than the sum of its proper divisors (6987341441).

21504334975 is a wasteful number, since it uses less digits than its factorization.

21504334975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7156 (or 7151 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 43.

The spelling of 21504334975 in words is "twenty-one billion, five hundred four million, three hundred thirty-four thousand, nine hundred seventy-five".