21597389774 has 4 divisors (see below), whose sum is σ = 32396084664. Its totient is φ = 10798694886.

The previous prime is 21597389761. The next prime is 21597389857. The reversal of 21597389774 is 47798379512.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5399347442 + ... + 5399347445.

It is an arithmetic number, because the mean of its divisors is an integer number (8099021166).

Almost surely, 2^21597389774 is an apocalyptic number.

21597389774 is a deficient number, since it is larger than the sum of its proper divisors (10798694890).

21597389774 is a wasteful number, since it uses less digits than its factorization.

21597389774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10798694889.

The product of its digits is 26671680, while the sum is 62.

The spelling of 21597389774 in words is "twenty-one billion, five hundred ninety-seven million, three hundred eighty-nine thousand, seven hundred seventy-four".