21643602405715 has 16 divisors (see below), whose sum is σ = 27380568268800. Its totient is φ = 16399819524960.

The previous prime is 21643602405707. The next prime is 21643602405721. The reversal of 21643602405715 is 51750420634612.

It is not a de Polignac number, because 21643602405715 - 2³ = 21643602405707 is a prime.

It is a super-2 number, since 2×21643602405715² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1485483615 + ... + 1485498184.

It is an arithmetic number, because the mean of its divisors is an integer number (1711285516800).

Almost surely, 2^{21643602405715} is an apocalyptic number.

21643602405715 is a deficient number, since it is larger than the sum of its proper divisors (5736965863085).

21643602405715 is a wasteful number, since it uses less digits than its factorization.

21643602405715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2970981882.

The product of its (nonzero) digits is 1209600, while the sum is 46.

The spelling of 21643602405715 in words is "twenty-one trillion, six hundred forty-three billion, six hundred two million, four hundred five thousand, seven hundred fifteen".