31220023 has 2 divisors, whose sum is σ = 31220024. Its totient is φ = 31220022.

The previous prime is 31220011. The next prime is 31220053. The reversal of 31220023 is 32002213.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31220023 is a prime.

It is a super-2 number, since 2×31220023² = 1949379672241058, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31219985 and 31220012.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31220003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610011 + 15610012.

It is an arithmetic number, because the mean of its divisors is an integer number (15610012).

Almost surely, 2^31220023 is an apocalyptic number.

31220023 is a deficient number, since it is larger than the sum of its proper divisors (1).

31220023 is an equidigital number, since it uses as much as digits as its factorization.

31220023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 13.

The square root of 31220023 is about 5587.4880760499. The cubic root of 31220023 is about 314.8795138432.

Adding to 31220023 its reverse (32002213), we get a palindrome (63222236).

The spelling of 31220023 in words is "thirty-one million, two hundred twenty thousand, twenty-three".