21839519524 has 27 divisors (see below), whose sum is σ = 40346938737. Its totient is φ = 10342375488.

The previous prime is 21839519519. The next prime is 21839519539. The reversal of 21839519524 is 42591593812.

The square root of 21839519524 is 147782.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 15830169124 + 6009350400 = 125818^2 + 77520^2 .

It is a super-2 number, since 2×21839519524² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5613772 + ... + 5617660.

Almost surely, 2^21839519524 is an apocalyptic number.

21839519524 is the 147782-nd square number.

It is an amenable number.

21839519524 is a deficient number, since it is larger than the sum of its proper divisors (18507419213).

21839519524 is an frugal number, since it uses more digits than its factorization.

21839519524 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7820 (or 3910 counting only the distinct ones).

The product of its digits is 777600, while the sum is 49.

Multiplying 21839519524 by its sum of digits (49), we get a square (1070136456676 = 1034474²).

The spelling of 21839519524 in words is "twenty-one billion, eight hundred thirty-nine million, five hundred nineteen thousand, five hundred twenty-four".