31125649 has 2 divisors, whose sum is σ = 31125650. Its totient is φ = 31125648.

The previous prime is 31125617. The next prime is 31125697. The reversal of 31125649 is 94652113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28462225 + 2663424 = 5335^2 + 1632^2 .

It is a cyclic number.

It is not a de Polignac number, because 31125649 - 2⁵ = 31125617 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31125649.

It is not a weakly prime, because it can be changed into another prime (31125349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15562824 + 15562825.

It is an arithmetic number, because the mean of its divisors is an integer number (15562825).

Almost surely, 2^31125649 is an apocalyptic number.

It is an amenable number.

31125649 is a deficient number, since it is larger than the sum of its proper divisors (1).

31125649 is an equidigital number, since it uses as much as digits as its factorization.

31125649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 31.

The square root of 31125649 is about 5579.0365655729. The cubic root of 31125649 is about 314.5619139001.

The spelling of 31125649 in words is "thirty-one million, one hundred twenty-five thousand, six hundred forty-nine".