231139501 has 2 divisors, whose sum is σ = 231139502. Its totient is φ = 231139500.

The previous prime is 231139499. The next prime is 231139507. The reversal of 231139501 is 105931132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220077225 + 11062276 = 14835^2 + 3326^2 .

It is a cyclic number.

It is not a de Polignac number, because 231139501 - 2¹ = 231139499 is a prime.

It is a super-3 number, since 3×231139501³ (a number of 26 digits) contains 333 as substring.

Together with 231139499, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231139507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115569750 + 115569751.

It is an arithmetic number, because the mean of its divisors is an integer number (115569751).

Almost surely, 2^231139501 is an apocalyptic number.

It is an amenable number.

231139501 is a deficient number, since it is larger than the sum of its proper divisors (1).

231139501 is an equidigital number, since it uses as much as digits as its factorization.

231139501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 810, while the sum is 25.

The square root of 231139501 is about 15203.2727068878. The cubic root of 231139501 is about 613.7027327016.

The spelling of 231139501 in words is "two hundred thirty-one million, one hundred thirty-nine thousand, five hundred one".