31800275161 has 2 divisors, whose sum is σ = 31800275162. Its totient is φ = 31800275160.

The previous prime is 31800275093. The next prime is 31800275173. The reversal of 31800275161 is 16157200813.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25550424025 + 6249851136 = 159845^2 + 79056^2 .

It is a cyclic number.

It is not a de Polignac number, because 31800275161 - 2²⁵ = 31766720729 is a prime.

It is a super-2 number, since 2×31800275161² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31800225161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15900137580 + 15900137581.

It is an arithmetic number, because the mean of its divisors is an integer number (15900137581).

Almost surely, 2^31800275161 is an apocalyptic number.

It is an amenable number.

31800275161 is a deficient number, since it is larger than the sum of its proper divisors (1).

31800275161 is an equidigital number, since it uses as much as digits as its factorization.

31800275161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 34.

Adding to 31800275161 its reverse (16157200813), we get a palindrome (47957475974).

The spelling of 31800275161 in words is "thirty-one billion, eight hundred million, two hundred seventy-five thousand, one hundred sixty-one".