21430553125 has 12 divisors (see below), whose sum is σ = 26786480868. Its totient is φ = 17144440000.

The previous prime is 21430553119. The next prime is 21430553147. The reversal of 21430553125 is 52135503412.

It can be written as a sum of positive squares in 6 ways, for example, as 16590985636 + 4839567489 = 128806^2 + 69567^2 .

It is not a de Polignac number, because 21430553125 - 2⁹ = 21430552613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3425764 + ... + 3432013.

It is an arithmetic number, because the mean of its divisors is an integer number (2232206739).

Almost surely, 2^21430553125 is an apocalyptic number.

21430553125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21430553125 is a deficient number, since it is larger than the sum of its proper divisors (5355927743).

21430553125 is an frugal number, since it uses more digits than its factorization.

21430553125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6857802 (or 6857782 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 31.

The spelling of 21430553125 in words is "twenty-one billion, four hundred thirty million, five hundred fifty-three thousand, one hundred twenty-five".