90900913 has 2 divisors, whose sum is σ = 90900914. Its totient is φ = 90900912.

The previous prime is 90900907. The next prime is 90900923. The reversal of 90900913 is 31900909.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84052224 + 6848689 = 9168^2 + 2617^2 .

It is an emirp because it is prime and its reverse (31900909) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90900913 - 2⁵ = 90900881 is a prime.

It is a super-3 number, since 3×90900913³ (a number of 25 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (90900923) 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 as a sum of consecutive naturals, namely, 45450456 + 45450457.

It is an arithmetic number, because the mean of its divisors is an integer number (45450457).

Almost surely, 2^90900913 is an apocalyptic number.

It is an amenable number.

90900913 is a deficient number, since it is larger than the sum of its proper divisors (1).

90900913 is an equidigital number, since it uses as much as digits as its factorization.

90900913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2187, while the sum is 31.

The square root of 90900913 is about 9534.1970296402. The cubic root of 90900913 is about 449.6308297338.

The spelling of 90900913 in words is "ninety million, nine hundred thousand, nine hundred thirteen".