168725420644 has 27 divisors (see below), whose sum is σ = 324569794003. Its totient is φ = 76689265400.

The previous prime is 168725420621. The next prime is 168725420657. The reversal of 168725420644 is 446024527861.

The square root of 168725420644 is 410762.

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

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9027429 + ... + 9046099.

Almost surely, 2^168725420644 is an apocalyptic number.

168725420644 is the 410762-nd square number.

It is an amenable number.

168725420644 is a deficient number, since it is larger than the sum of its proper divisors (155844373359).

168725420644 is an frugal number, since it uses more digits than its factorization.

168725420644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37368 (or 18684 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 49.

Multiplying 168725420644 by its sum of digits (49), we get a square (8267545611556 = 2875334²).

The spelling of 168725420644 in words is "one hundred sixty-eight billion, seven hundred twenty-five million, four hundred twenty thousand, six hundred forty-four".