31136620409 has 2 divisors, whose sum is σ = 31136620410. Its totient is φ = 31136620408.

The previous prime is 31136620349. The next prime is 31136620421. The reversal of 31136620409 is 90402663113.

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., 17258602384 + 13878018025 = 131372^2 + 117805^2 .

It is a cyclic number.

It is not a de Polignac number, because 31136620409 - 2²⁴ = 31119843193 is a prime.

It is not a weakly prime, because it can be changed into another prime (31136620469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15568310204 + 15568310205.

It is an arithmetic number, because the mean of its divisors is an integer number (15568310205).

Almost surely, 2^31136620409 is an apocalyptic number.

It is an amenable number.

31136620409 is a deficient number, since it is larger than the sum of its proper divisors (1).

31136620409 is an equidigital number, since it uses as much as digits as its factorization.

31136620409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 35.

The spelling of 31136620409 in words is "thirty-one billion, one hundred thirty-six million, six hundred twenty thousand, four hundred nine".