90918013 has 2 divisors, whose sum is σ = 90918014. Its totient is φ = 90918012.

The previous prime is 90917993. The next prime is 90918029. The reversal of 90918013 is 31081909.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85433049 + 5484964 = 9243^2 + 2342^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90918013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90918043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45459006 + 45459007.

It is an arithmetic number, because the mean of its divisors is an integer number (45459007).

Almost surely, 2^90918013 is an apocalyptic number.

It is an amenable number.

90918013 is a deficient number, since it is larger than the sum of its proper divisors (1).

90918013 is an equidigital number, since it uses as much as digits as its factorization.

90918013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 90918013 is about 9535.0937593712. The cubic root of 90918013 is about 449.6590223554.

The spelling of 90918013 in words is "ninety million, nine hundred eighteen thousand, thirteen".