165742623225 has 135 divisors (see below), whose sum is σ = 313633274493. Its totient is φ = 86529850560.

The previous prime is 165742623199. The next prime is 165742623239. The reversal of 165742623225 is 522326247561.

The square root of 165742623225 is 407115.

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

165742623225 is a `hidden beast` number, since 1 + 6 + 574 + 26 + 2 + 32 + 25 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 607671801 + 165134951424 = 24651^2 + 406368^2 .

It is a tau number, because it is divible by the number of its divisors (135).

It is not a de Polignac number, because 165742623225 - 2¹⁵ = 165742590457 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

Its product of digits (1209600) is a multiple of the sum of its prime divisors (200).

It is an unprimeable number.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 1520574471 + ... + 1520574579.

Almost surely, 2^165742623225 is an apocalyptic number.

165742623225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

165742623225 is the 407115-th square number.

165742623225 is the 203558-th centered octagonal number.

It is an amenable number.

165742623225 is a deficient number, since it is larger than the sum of its proper divisors (147890651268).

165742623225 is an frugal number, since it uses more digits than its factorization.

165742623225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406 (or 200 counting only the distinct ones).

The product of its digits is 1209600, while the sum is 45.

The spelling of 165742623225 in words is "one hundred sixty-five billion, seven hundred forty-two million, six hundred twenty-three thousand, two hundred twenty-five".