21405427683 has 16 divisors (see below), whose sum is σ = 30050791680. Its totient is φ = 13515578784.

The previous prime is 21405427661. The next prime is 21405427709. The reversal of 21405427683 is 38672450412.

It is not a de Polignac number, because 21405427683 - 2²⁶ = 21338318819 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21405427613) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 171585 + ... + 268797.

It is an arithmetic number, because the mean of its divisors is an integer number (1878174480).

Almost surely, 2^21405427683 is an apocalyptic number.

21405427683 is a deficient number, since it is larger than the sum of its proper divisors (8645363997).

21405427683 is a wasteful number, since it uses less digits than its factorization.

21405427683 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101098.

The product of its (nonzero) digits is 322560, while the sum is 42.

The spelling of 21405427683 in words is "twenty-one billion, four hundred five million, four hundred twenty-seven thousand, six hundred eighty-three".