21504854375 has 10 divisors (see below), whose sum is σ = 26872466808. Its totient is φ = 17203883000.

The previous prime is 21504854339. The next prime is 21504854377. The reversal of 21504854375 is 57345840512.

It is not a de Polignac number, because 21504854375 - 2¹⁰ = 21504853351 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21504854377) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 17203259 + ... + 17204508.

Almost surely, 2^21504854375 is an apocalyptic number.

21504854375 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21504854375 is a deficient number, since it is larger than the sum of its proper divisors (5367612433).

21504854375 is an frugal number, since it uses more digits than its factorization.

21504854375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34407787 (or 34407772 counting only the distinct ones).

The product of its (nonzero) digits is 672000, while the sum is 44.

The spelling of 21504854375 in words is "twenty-one billion, five hundred four million, eight hundred fifty-four thousand, three hundred seventy-five".