90444421 has 4 divisors (see below), whose sum is σ = 90918144. Its totient is φ = 89970700.

The previous prime is 90444407. The next prime is 90444451. The reversal of 90444421 is 12444409.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12444409 = 173 ⋅71933.

It is a cyclic number.

It is not a de Polignac number, because 90444421 - 2¹⁵ = 90411653 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 90444421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90444451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 236575 + ... + 236956.

It is an arithmetic number, because the mean of its divisors is an integer number (22729536).

Almost surely, 2^90444421 is an apocalyptic number.

It is an amenable number.

90444421 is a deficient number, since it is larger than the sum of its proper divisors (473723).

90444421 is a wasteful number, since it uses less digits than its factorization.

90444421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473722.

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 90444421 is about 9510.2271792003. The cubic root of 90444421 is about 448.8769046971.

The spelling of 90444421 in words is "ninety million, four hundred forty-four thousand, four hundred twenty-one".