21870512875 has 16 divisors (see below), whose sum is σ = 28730950560. Its totient is φ = 16575544800.

The previous prime is 21870512843. The next prime is 21870512887. The reversal of 21870512875 is 57821507812.

It is not a de Polignac number, because 21870512875 - 2⁵ = 21870512843 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 4601944 + ... + 4606693.

It is an arithmetic number, because the mean of its divisors is an integer number (1795684410).

Almost surely, 2^21870512875 is an apocalyptic number.

21870512875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21870512875 is a deficient number, since it is larger than the sum of its proper divisors (6860437685).

21870512875 is an equidigital number, since it uses as much as digits as its factorization.

21870512875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9208671 (or 9208661 counting only the distinct ones).

The product of its (nonzero) digits is 313600, while the sum is 46.

The spelling of 21870512875 in words is "twenty-one billion, eight hundred seventy million, five hundred twelve thousand, eight hundred seventy-five".