161125974025 has 27 divisors (see below), whose sum is σ = 204660307431. Its totient is φ = 125835650640.

The previous prime is 161125974019. The next prime is 161125974029. The reversal of 161125974025 is 520479521161.

The square root of 161125974025 is 401405.

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., 58005350649 + 103120623376 = 240843^2 + 321124^2 .

It is not a de Polignac number, because 161125974025 - 2²⁷ = 160991756297 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161125974029) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 86301142 + ... + 86303008.

Almost surely, 2^161125974025 is an apocalyptic number.

161125974025 is the 401405-th square number.

161125974025 is the 200703-rd centered octagonal number.

It is an amenable number.

161125974025 is a deficient number, since it is larger than the sum of its proper divisors (43534333406).

161125974025 is an frugal number, since it uses more digits than its factorization.

161125974025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3830 (or 1915 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 43.

The spelling of 161125974025 in words is "one hundred sixty-one billion, one hundred twenty-five million, nine hundred seventy-four thousand, twenty-five".