90886921 has 4 divisors (see below), whose sum is σ = 91210644. Its totient is φ = 90563200.

The previous prime is 90886919. The next prime is 90886931. The reversal of 90886921 is 12968809.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12968809 = 7 ⋅1852687.

It can be written as a sum of positive squares in 2 ways, for example, as 44156025 + 46730896 = 6645^2 + 6836^2 .

It is a cyclic number.

It is not a de Polignac number, because 90886921 - 2¹ = 90886919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90886931) 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 3 ways as a sum of consecutive naturals, for example, 161440 + ... + 162001.

It is an arithmetic number, because the mean of its divisors is an integer number (22802661).

Almost surely, 2^90886921 is an apocalyptic number.

It is an amenable number.

90886921 is a deficient number, since it is larger than the sum of its proper divisors (323723).

90886921 is a wasteful number, since it uses less digits than its factorization.

90886921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323722.

The product of its (nonzero) digits is 62208, while the sum is 43.

The square root of 90886921 is about 9533.4632217259. The cubic root of 90886921 is about 449.6077586146.

The spelling of 90886921 in words is "ninety million, eight hundred eighty-six thousand, nine hundred twenty-one".