31120009 has 2 divisors, whose sum is σ = 31120010. Its totient is φ = 31120008.

The previous prime is 31119983. The next prime is 31120027. The reversal of 31120009 is 90002113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29942784 + 1177225 = 5472^2 + 1085^2 .

It is a cyclic number.

It is not a de Polignac number, because 31120009 - 2²¹ = 29022857 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31119974 and 31120001.

It is not a weakly prime, because it can be changed into another prime (31120039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15560004 + 15560005.

It is an arithmetic number, because the mean of its divisors is an integer number (15560005).

Almost surely, 2^31120009 is an apocalyptic number.

It is an amenable number.

31120009 is a deficient number, since it is larger than the sum of its proper divisors (1).

31120009 is an equidigital number, since it uses as much as digits as its factorization.

31120009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 31120009 is about 5578.5310790566. The cubic root of 31120009 is about 314.5429131037.

The spelling of 31120009 in words is "thirty-one million, one hundred twenty thousand, nine".