21487993375 has 16 divisors (see below), whose sum is σ = 26824112640. Its totient is φ = 17185845600.

The previous prime is 21487993367. The next prime is 21487993393. The reversal of 21487993375 is 57339978412.

It is not a de Polignac number, because 21487993375 - 2³ = 21487993367 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 499209 + ... + 540541.

It is an arithmetic number, because the mean of its divisors is an integer number (1676507040).

Almost surely, 2^21487993375 is an apocalyptic number.

21487993375 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21487993375 is a deficient number, since it is larger than the sum of its proper divisors (5336119265).

21487993375 is an equidigital number, since it uses as much as digits as its factorization.

21487993375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45507 (or 45497 counting only the distinct ones).

The product of its digits is 11430720, while the sum is 58.

The spelling of 21487993375 in words is "twenty-one billion, four hundred eighty-seven million, nine hundred ninety-three thousand, three hundred seventy-five".