21573750231 has 24 divisors (see below), whose sum is σ = 34095928464. Its totient is φ = 13036181760.

The previous prime is 21573750217. The next prime is 21573750251. The reversal of 21573750231 is 13205737512.

It is a happy number.

21573750231 is a `hidden beast` number, since 2 + 1 + 57 + 375 + 0 + 231 = 666.

It is not a de Polignac number, because 21573750231 - 2⁵ = 21573750199 is a prime.

It is a super-2 number, since 2×21573750231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21573750251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 289956 + ... + 356681.

It is an arithmetic number, because the mean of its divisors is an integer number (1420663686).

Almost surely, 2^21573750231 is an apocalyptic number.

21573750231 is a deficient number, since it is larger than the sum of its proper divisors (12522178233).

21573750231 is a wasteful number, since it uses less digits than its factorization.

21573750231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646991 (or 646988 counting only the distinct ones).

The product of its (nonzero) digits is 44100, while the sum is 36.

The spelling of 21573750231 in words is "twenty-one billion, five hundred seventy-three million, seven hundred fifty thousand, two hundred thirty-one".