31312312261 has 2 divisors, whose sum is σ = 31312312262. Its totient is φ = 31312312260.

The previous prime is 31312312247. The next prime is 31312312319. The reversal of 31312312261 is 16221321313.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31150132036 + 162180225 = 176494^2 + 12735^2 .

It is a cyclic number.

It is not a de Polignac number, because 31312312261 - 2⁹ = 31312311749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31312312211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656156130 + 15656156131.

It is an arithmetic number, because the mean of its divisors is an integer number (15656156131).

Almost surely, 2^31312312261 is an apocalyptic number.

It is an amenable number.

31312312261 is a deficient number, since it is larger than the sum of its proper divisors (1).

31312312261 is an equidigital number, since it uses as much as digits as its factorization.

31312312261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 25.

Adding to 31312312261 its reverse (16221321313), we get a palindrome (47533633574).

The spelling of 31312312261 in words is "thirty-one billion, three hundred twelve million, three hundred twelve thousand, two hundred sixty-one".