31545020231 has 2 divisors, whose sum is σ = 31545020232. Its totient is φ = 31545020230.

The previous prime is 31545020201. The next prime is 31545020239. The reversal of 31545020231 is 13202054513.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31545020231 - 2³⁰ = 30471278407 is a prime.

It is a super-2 number, since 2×31545020231² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31545020231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31545020239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15772510115 + 15772510116.

It is an arithmetic number, because the mean of its divisors is an integer number (15772510116).

Almost surely, 2^31545020231 is an apocalyptic number.

31545020231 is a deficient number, since it is larger than the sum of its proper divisors (1).

31545020231 is an equidigital number, since it uses as much as digits as its factorization.

31545020231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 26.

Adding to 31545020231 its reverse (13202054513), we get a palindrome (44747074744).

The spelling of 31545020231 in words is "thirty-one billion, five hundred forty-five million, twenty thousand, two hundred thirty-one".