31100123009 has 2 divisors, whose sum is σ = 31100123010. Its totient is φ = 31100123008.

The previous prime is 31100122987. The next prime is 31100123023. The reversal of 31100123009 is 90032100113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30922167409 + 177955600 = 175847^2 + 13340^2 .

It is a cyclic number.

It is not a de Polignac number, because 31100123009 - 2¹⁶ = 31100057473 is a prime.

It is not a weakly prime, because it can be changed into another prime (31100123029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15550061504 + 15550061505.

It is an arithmetic number, because the mean of its divisors is an integer number (15550061505).

Almost surely, 2^31100123009 is an apocalyptic number.

It is an amenable number.

31100123009 is a deficient number, since it is larger than the sum of its proper divisors (1).

31100123009 is an equidigital number, since it uses as much as digits as its factorization.

31100123009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 20.

The spelling of 31100123009 in words is "thirty-one billion, one hundred million, one hundred twenty-three thousand, nine".