90131810 has 16 divisors (see below), whose sum is σ = 162388800. Its totient is φ = 36019056.

The previous prime is 90131777. The next prime is 90131819. The reversal of 90131810 is 1813109.

It is a super-2 number, since 2×90131810² = 16247486347752200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (90131819) 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, 9011 + ... + 16169.

It is an arithmetic number, because the mean of its divisors is an integer number (10149300).

Almost surely, 2^90131810 is an apocalyptic number.

90131810 is a deficient number, since it is larger than the sum of its proper divisors (72256990).

90131810 is a wasteful number, since it uses less digits than its factorization.

90131810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8425.

The product of its (nonzero) digits is 216, while the sum is 23.

The square root of 90131810 is about 9493.7774357734. Note that the first 3 decimals coincide. The cubic root of 90131810 is about 448.3591434802.

Adding to 90131810 its reverse (1813109), we get a palindrome (91944919).

The spelling of 90131810 in words is "ninety million, one hundred thirty-one thousand, eight hundred ten".