725457620644 has 9 divisors (see below), whose sum is σ = 1269553817217. Its totient is φ = 362727958584.

The previous prime is 725457620597. The next prime is 725457620653. The reversal of 725457620644 is 446026754527.

The square root of 725457620644 is 851738.

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., 173170835044 + 552286785600 = 416138^2 + 743160^2 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 725457620591 and 725457620600.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1490542 + ... + 1916410.

Almost surely, 2^725457620644 is an apocalyptic number.

725457620644 is the 851738-th square number.

It is an amenable number.

725457620644 is a deficient number, since it is larger than the sum of its proper divisors (544096196573).

725457620644 is an frugal number, since it uses more digits than its factorization.

725457620644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 851742 (or 425871 counting only the distinct ones).

The product of its (nonzero) digits is 11289600, while the sum is 52.

The spelling of 725457620644 in words is "seven hundred twenty-five billion, four hundred fifty-seven million, six hundred twenty thousand, six hundred forty-four".