31389901 has 2 divisors, whose sum is σ = 31389902. Its totient is φ = 31389900.

The previous prime is 31389893. The next prime is 31389907. The reversal of 31389901 is 10998313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29702500 + 1687401 = 5450^2 + 1299^2 .

It is a cyclic number.

It is not a de Polignac number, because 31389901 - 2³ = 31389893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31389907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15694950 + 15694951.

It is an arithmetic number, because the mean of its divisors is an integer number (15694951).

Almost surely, 2^31389901 is an apocalyptic number.

It is an amenable number.

31389901 is a deficient number, since it is larger than the sum of its proper divisors (1).

31389901 is an equidigital number, since it uses as much as digits as its factorization.

31389901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 34.

The square root of 31389901 is about 5602.6690960648. The cubic root of 31389901 is about 315.4496006923.

The spelling of 31389901 in words is "thirty-one million, three hundred eighty-nine thousand, nine hundred one".