31090901 has 2 divisors, whose sum is σ = 31090902. Its totient is φ = 31090900.

The previous prime is 31090889. The next prime is 31090903. The reversal of 31090901 is 10909013.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24990001 + 6100900 = 4999^2 + 2470^2 .

It is a cyclic number.

It is not a de Polignac number, because 31090901 - 2⁶ = 31090837 is a prime.

Together with 31090903, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31090903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15545450 + 15545451.

It is an arithmetic number, because the mean of its divisors is an integer number (15545451).

Almost surely, 2^31090901 is an apocalyptic number.

It is an amenable number.

31090901 is a deficient number, since it is larger than the sum of its proper divisors (1).

31090901 is an equidigital number, since it uses as much as digits as its factorization.

31090901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 243, while the sum is 23.

The square root of 31090901 is about 5575.9215381854. The cubic root of 31090901 is about 314.4448136120. Note that the first 3 decimals are identical.

Adding to 31090901 its reverse (10909013), we get a palindrome (41999914).

The spelling of 31090901 in words is "thirty-one million, ninety thousand, nine hundred one".