31949917 has 2 divisors, whose sum is σ = 31949918. Its totient is φ = 31949916.

The previous prime is 31949899. The next prime is 31949927. The reversal of 31949917 is 71994913.

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., 18156121 + 13793796 = 4261^2 + 3714^2 .

It is an emirp because it is prime and its reverse (71994913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31949917 - 2¹⁹ = 31425629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31949927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15974958 + 15974959.

It is an arithmetic number, because the mean of its divisors is an integer number (15974959).

Almost surely, 2^31949917 is an apocalyptic number.

It is an amenable number.

31949917 is a deficient number, since it is larger than the sum of its proper divisors (1).

31949917 is an equidigital number, since it uses as much as digits as its factorization.

31949917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 61236, while the sum is 43.

The square root of 31949917 is about 5652.4257624493. The cubic root of 31949917 is about 317.3144951459.

The spelling of 31949917 in words is "thirty-one million, nine hundred forty-nine thousand, nine hundred seventeen".