28507620964 has 9 divisors (see below), whose sum is σ = 49888927641. Its totient is φ = 14253641640.

The previous prime is 28507620961. The next prime is 28507620971. The reversal of 28507620964 is 46902670582.

The square root of 28507620964 is 168842.

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., 27304918564 + 1202702400 = 165242^2 + 34680^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28507620961) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 295474 + ... + 379894.

Almost surely, 2^28507620964 is an apocalyptic number.

28507620964 is the 168842-nd square number.

It is an amenable number.

28507620964 is a deficient number, since it is larger than the sum of its proper divisors (21381306677).

28507620964 is an frugal number, since it uses more digits than its factorization.

28507620964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168846 (or 84423 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 49.

Multiplying 28507620964 by its sum of digits (49), we get a square (1396873427236 = 1181894²).

The spelling of 28507620964 in words is "twenty-eight billion, five hundred seven million, six hundred twenty thousand, nine hundred sixty-four".