31315201 has 2 divisors, whose sum is σ = 31315202. Its totient is φ = 31315200.

The previous prime is 31315199. The next prime is 31315231. The reversal of 31315201 is 10251313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30636225 + 678976 = 5535^2 + 824^2 .

It is a cyclic number.

It is not a de Polignac number, because 31315201 - 2¹ = 31315199 is a prime.

Together with 31315199, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31315231) 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, 15657600 + 15657601.

It is an arithmetic number, because the mean of its divisors is an integer number (15657601).

Almost surely, 2^31315201 is an apocalyptic number.

It is an amenable number.

31315201 is a deficient number, since it is larger than the sum of its proper divisors (1).

31315201 is an equidigital number, since it uses as much as digits as its factorization.

31315201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 31315201 is about 5595.9986597568. The cubic root of 31315201 is about 315.1991719307.

Adding to 31315201 its reverse (10251313), we get a palindrome (41566514).

The spelling of 31315201 in words is "thirty-one million, three hundred fifteen thousand, two hundred one".