21079861264 has 80 divisors (see below), whose sum is σ = 51132191616. Its totient is φ = 8178739200.

The previous prime is 21079861207. The next prime is 21079861303. The reversal of 21079861264 is 46216897012.

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, 261414 + ... + 332410.

Almost surely, 2^21079861264 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21079861264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25566095808).

21079861264 is an abundant number, since it is smaller than the sum of its proper divisors (30052330352).

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

21079861264 is a wasteful number, since it uses less digits than its factorization.

21079861264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71264 (or 71258 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 46.

The spelling of 21079861264 in words is "twenty-one billion, seventy-nine million, eight hundred sixty-one thousand, two hundred sixty-four".