492577981921 has 9 divisors (see below), whose sum is σ = 494239192083. Its totient is φ = 490922343720.

The previous prime is 492577981913. The next prime is 492577981943. The reversal of 492577981921 is 129189775294.

The square root of 492577981921 is 701839.

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., 361548461521 + 131029520400 = 601289^2 + 361980^2 .

It is not a de Polignac number, because 492577981921 - 2³ = 492577981913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (492577981901) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 244940806 + ... + 244942816.

It is an arithmetic number, because the mean of its divisors is an integer number (54915465787).

Almost surely, 2^492577981921 is an apocalyptic number.

492577981921 is the 701839-th square number.

492577981921 is the 350920-th centered octagonal number.

It is an amenable number.

492577981921 is a deficient number, since it is larger than the sum of its proper divisors (1661210162).

492577981921 is an frugal number, since it uses more digits than its factorization.

492577981921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4720 (or 2360 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 64.

Multiplying 492577981921 by its sum of digits (64), we get a square (31524990842944 = 5614712²).

The spelling of 492577981921 in words is "four hundred ninety-two billion, five hundred seventy-seven million, nine hundred eighty-one thousand, nine hundred twenty-one".