31220313 has 16 divisors (see below), whose sum is σ = 44421696. Its totient is φ = 19435520.

The previous prime is 31220297. The next prime is 31220377. The reversal of 31220313 is 31302213.

It is a cyclic number.

It is not a de Polignac number, because 31220313 - 2⁴ = 31220297 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31220292 and 31220301.

It is not an unprimeable number, because it can be changed into a prime (31220383) 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 in 15 ways as a sum of consecutive naturals, for example, 4345 + ... + 9017.

It is an arithmetic number, because the mean of its divisors is an integer number (2776356).

Almost surely, 2^31220313 is an apocalyptic number.

It is an amenable number.

31220313 is a deficient number, since it is larger than the sum of its proper divisors (13201383).

31220313 is a wasteful number, since it uses less digits than its factorization.

31220313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4824.

The product of its (nonzero) digits is 108, while the sum is 15.

The square root of 31220313 is about 5587.5140268280. The cubic root of 31220313 is about 314.8804888027.

Adding to 31220313 its reverse (31302213), we get a palindrome (62522526).

The spelling of 31220313 in words is "thirty-one million, two hundred twenty thousand, three hundred thirteen".