31345081 has 2 divisors, whose sum is σ = 31345082. Its totient is φ = 31345080.

The previous prime is 31345073. The next prime is 31345121. The reversal of 31345081 is 18054313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31181056 + 164025 = 5584^2 + 405^2 .

It is a cyclic number.

It is not a de Polignac number, because 31345081 - 2³ = 31345073 is a prime.

It is a super-2 number, since 2×31345081² = 1965028205793122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31345001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15672540 + 15672541.

It is an arithmetic number, because the mean of its divisors is an integer number (15672541).

Almost surely, 2^31345081 is an apocalyptic number.

It is an amenable number.

31345081 is a deficient number, since it is larger than the sum of its proper divisors (1).

31345081 is an equidigital number, since it uses as much as digits as its factorization.

31345081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 31345081 is about 5598.6677879653. The cubic root of 31345081 is about 315.2993911750.

Adding to 31345081 its reverse (18054313), we get a palindrome (49399394).

The spelling of 31345081 in words is "thirty-one million, three hundred forty-five thousand, eighty-one".