90685181 has 4 divisors (see below), whose sum is σ = 90705792. Its totient is φ = 90664572.

The previous prime is 90685121. The next prime is 90685211. The reversal of 90685181 is 18158609.

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 not a de Polignac number, because 90685181 - 2¹⁰ = 90684157 is a prime.

It is a super-2 number, since 2×90685181² = 16447604106005522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90685121) 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, 755 + ... + 13488.

It is an arithmetic number, because the mean of its divisors is an integer number (22676448).

Almost surely, 2^90685181 is an apocalyptic number.

It is an amenable number.

90685181 is a deficient number, since it is larger than the sum of its proper divisors (20611).

90685181 is a wasteful number, since it uses less digits than its factorization.

90685181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20610.

The product of its (nonzero) digits is 17280, while the sum is 38.

The square root of 90685181 is about 9522.8767187232. The cubic root of 90685181 is about 449.2748501964.

The spelling of 90685181 in words is "ninety million, six hundred eighty-five thousand, one hundred eighty-one".