90421081 has 9 divisors (see below), whose sum is σ = 93293949. Its totient is φ = 87634944.

The previous prime is 90421061. The next prime is 90421103. The reversal of 90421081 is 18012409.

It is a happy number.

The square root of 90421081 is 9509.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 72948681 + 17472400 = 8541^2 + 4180^2 .

It is not a de Polignac number, because 90421081 - 2²³ = 82032473 is a prime.

It is a super-2 number, since 2×90421081² = 16351943778417122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90421061) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 351705 + ... + 351961.

Almost surely, 2^90421081 is an apocalyptic number.

90421081 is the 9509-th square number.

90421081 is the 4755-th centered octagonal number.

It is an amenable number.

90421081 is a deficient number, since it is larger than the sum of its proper divisors (2872868).

90421081 is an frugal number, since it uses more digits than its factorization.

90421081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 588 (or 294 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 25.

The cubic root of 90421081 is about 448.8382891282.

Multiplying 90421081 by its sum of digits (25), we get a square (2260527025 = 47545²).

Multiplying 90421081 by its product of nonzero digits (576), we get a square (52082542656 = 228216²).

The spelling of 90421081 in words is "ninety million, four hundred twenty-one thousand, eighty-one".