21398815594 has 16 divisors (see below), whose sum is σ = 35682393600. Its totient is φ = 9557783280.

The previous prime is 21398815541. The next prime is 21398815609. The reversal of 21398815594 is 49551889312.

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, 13273894 + ... + 13275505.

It is an arithmetic number, because the mean of its divisors is an integer number (2230149600).

Almost surely, 2^21398815594 is an apocalyptic number.

21398815594 is a deficient number, since it is larger than the sum of its proper divisors (14283578006).

21398815594 is a wasteful number, since it uses less digits than its factorization.

21398815594 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26549445.

The product of its digits is 3110400, while the sum is 55.

The spelling of 21398815594 in words is "twenty-one billion, three hundred ninety-eight million, eight hundred fifteen thousand, five hundred ninety-four".