309186042025 has 27 divisors (see below), whose sum is σ = 446013164919. Its totient is φ = 211999940880.

The previous prime is 309186042023. The next prime is 309186042031. The reversal of 309186042025 is 520240681903.

The square root of 309186042025 is 556045.

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., 111306975129 + 197879066896 = 333627^2 + 444836^2 .

It is not a de Polignac number, because 309186042025 - 2¹ = 309186042023 is a prime.

It is a super-2 number, since 2×309186042025² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (309186042023) 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, 19453632 + ... + 19469518.

Almost surely, 2^309186042025 is an apocalyptic number.

309186042025 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

309186042025 is the 556045-th square number.

309186042025 is the 278023-rd centered octagonal number.

It is an amenable number.

309186042025 is a deficient number, since it is larger than the sum of its proper divisors (136827122894).

309186042025 is an frugal number, since it uses more digits than its factorization.

309186042025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31798 (or 15899 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 40.

The spelling of 309186042025 in words is "three hundred nine billion, one hundred eighty-six million, forty-two thousand, twenty-five".