21261075708 has 48 divisors (see below), whose sum is σ = 51949207296. Its totient is φ = 6754915200.

The previous prime is 21261075707. The next prime is 21261075713. The reversal of 21261075708 is 80757016212.

It is a super-2 number, since 2×21261075708² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21261075707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57993 + ... + 214208.

It is an arithmetic number, because the mean of its divisors is an integer number (1082275152).

Almost surely, 2^21261075708 is an apocalyptic number.

It is an amenable number.

21261075708 is an abundant number, since it is smaller than the sum of its proper divisors (30688131588).

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

21261075708 is a wasteful number, since it uses less digits than its factorization.

21261075708 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272514 (or 272512 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 39.

The spelling of 21261075708 in words is "twenty-one billion, two hundred sixty-one million, seventy-five thousand, seven hundred eight".