90109621 has 8 divisors (see below), whose sum is σ = 103079744. Its totient is φ = 77163840.

The previous prime is 90109619. The next prime is 90109637. The reversal of 90109621 is 12690109.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90109621 - 2¹ = 90109619 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90109621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90109651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2701 + ... + 13693.

It is an arithmetic number, because the mean of its divisors is an integer number (12884968).

Almost surely, 2^90109621 is an apocalyptic number.

It is an amenable number.

90109621 is a deficient number, since it is larger than the sum of its proper divisors (12970123).

90109621 is a wasteful number, since it uses less digits than its factorization.

90109621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12171.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 90109621 is about 9492.6087562903. The cubic root of 90109621 is about 448.3223475271.

The spelling of 90109621 in words is "ninety million, one hundred nine thousand, six hundred twenty-one".