231806620369 has 9 divisors (see below), whose sum is σ = 237618573339. Its totient is φ = 226133541840.

The previous prime is 231806620337. The next prime is 231806620403. The reversal of 231806620369 is 963026608132.

It is a happy number.

The square root of 231806620369 is 481463.

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., 11169741969 + 220636878400 = 105687^2 + 469720^2 .

It is not a de Polignac number, because 231806620369 - 2⁵ = 231806620337 is a prime.

It is a super-2 number, since 2×231806620369² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231806620319) 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, 19734112 + ... + 19745854.

Almost surely, 2^231806620369 is an apocalyptic number.

231806620369 is the 481463-rd square number.

231806620369 is the 240732-nd centered octagonal number.

It is an amenable number.

231806620369 is a deficient number, since it is larger than the sum of its proper divisors (5811952970).

231806620369 is an frugal number, since it uses more digits than its factorization.

231806620369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23568 (or 11784 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 46.

The spelling of 231806620369 in words is "two hundred thirty-one billion, eight hundred six million, six hundred twenty thousand, three hundred sixty-nine".