90645281 has 4 divisors (see below), whose sum is σ = 92573952. Its totient is φ = 88716612.

The previous prime is 90645259. The next prime is 90645283. The reversal of 90645281 is 18254609.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90645281 is a prime.

It is a super-2 number, since 2×90645281² = 16433133935137922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90645283) 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, 964265 + ... + 964358.

It is an arithmetic number, because the mean of its divisors is an integer number (23143488).

Almost surely, 2^90645281 is an apocalyptic number.

It is an amenable number.

90645281 is a deficient number, since it is larger than the sum of its proper divisors (1928671).

90645281 is a wasteful number, since it uses less digits than its factorization.

90645281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1928670.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 90645281 is about 9520.7815330465. The cubic root of 90645281 is about 449.2089493291.

The spelling of 90645281 in words is "ninety million, six hundred forty-five thousand, two hundred eighty-one".