231533531202551 has 4 divisors (see below), whose sum is σ = 245153150685072. Its totient is φ = 217913911720032.

The previous prime is 231533531202539. The next prime is 231533531202601. The reversal of 231533531202551 is 155202135335132.

231533531202551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 231533531202551 - 2²² = 231533527008247 is a prime.

It is a super-2 number, since 2×231533531202551² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 231533531202499 and 231533531202508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231533531202511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6809809741235 + ... + 6809809741268.

It is an arithmetic number, because the mean of its divisors is an integer number (61288287671268).

Almost surely, 2^{231533531202551} is an apocalyptic number.

231533531202551 is a deficient number, since it is larger than the sum of its proper divisors (13619619482521).

231533531202551 is a wasteful number, since it uses less digits than its factorization.

231533531202551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13619619482520.

The product of its (nonzero) digits is 405000, while the sum is 41.

Adding to 231533531202551 its reverse (155202135335132), we get a palindrome (386735666537683).

The spelling of 231533531202551 in words is "two hundred thirty-one trillion, five hundred thirty-three billion, five hundred thirty-one million, two hundred two thousand, five hundred fifty-one".