31402313 has 2 divisors, whose sum is σ = 31402314. Its totient is φ = 31402312.

The previous prime is 31402309. The next prime is 31402321. The reversal of 31402313 is 31320413.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25775929 + 5626384 = 5077^2 + 2372^2 .

It is an emirp because it is prime and its reverse (31320413) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31402313 - 2² = 31402309 is a prime.

It is a super-2 number, since 2×31402313² = 1972210523499938, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31402291 and 31402300.

It is not a weakly prime, because it can be changed into another prime (31402333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15701156 + 15701157.

It is an arithmetic number, because the mean of its divisors is an integer number (15701157).

Almost surely, 2^31402313 is an apocalyptic number.

It is an amenable number.

31402313 is a deficient number, since it is larger than the sum of its proper divisors (1).

31402313 is an equidigital number, since it uses as much as digits as its factorization.

31402313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 31402313 is about 5603.7766729234. The cubic root of 31402313 is about 315.4911729217.

Adding to 31402313 its reverse (31320413), we get a palindrome (62722726).

The spelling of 31402313 in words is "thirty-one million, four hundred two thousand, three hundred thirteen".