21375651810 has 16 divisors (see below), whose sum is σ = 51301564416. Its totient is φ = 5700173808.

The previous prime is 21375651779. The next prime is 21375651821. The reversal of 21375651810 is 1815657312.

It is a super-2 number, since 2×21375651810² (a number of 21 digits) contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 356260834 + ... + 356260893.

It is an arithmetic number, because the mean of its divisors is an integer number (3206347776).

Almost surely, 2^21375651810 is an apocalyptic number.

21375651810 is an abundant number, since it is smaller than the sum of its proper divisors (29925912606).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21375651810 is a wasteful number, since it uses less digits than its factorization.

21375651810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 712521737.

The product of its (nonzero) digits is 50400, while the sum is 39.

The spelling of 21375651810 in words is "twenty-one billion, three hundred seventy-five million, six hundred fifty-one thousand, eight hundred ten".