21408881260730 has 16 divisors (see below), whose sum is σ = 38933264480040. Its totient is φ = 8475268457472.

The previous prime is 21408881260651. The next prime is 21408881260777. The reversal of 21408881260730 is 3706218880412.

It can be written as a sum of positive squares in 4 ways, for example, as 21021152123689 + 387729137041 = 4584883^2 + 622679^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11035504835 + ... + 11035506774.

Almost surely, 2^{21408881260730} is an apocalyptic number.

21408881260730 is a deficient number, since it is larger than the sum of its proper divisors (17524383219310).

21408881260730 is a wasteful number, since it uses less digits than its factorization.

21408881260730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22071011713.

The product of its (nonzero) digits is 1032192, while the sum is 50.

The spelling of 21408881260730 in words is "twenty-one trillion, four hundred eight billion, eight hundred eighty-one million, two hundred sixty thousand, seven hundred thirty".