90131993 has 8 divisors (see below), whose sum is σ = 103226880. Its totient is φ = 77091840.

The previous prime is 90131989. The next prime is 90132001. The reversal of 90131993 is 39913109.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 90131993 - 2² = 90131989 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (90130993) 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, 10088 + ... + 16793.

It is an arithmetic number, because the mean of its divisors is an integer number (12903360).

Almost surely, 2^90131993 is an apocalyptic number.

It is an amenable number.

90131993 is a deficient number, since it is larger than the sum of its proper divisors (13094887).

90131993 is a wasteful number, since it uses less digits than its factorization.

90131993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27367.

The product of its (nonzero) digits is 6561, while the sum is 35.

The square root of 90131993 is about 9493.7870736603. The cubic root of 90131993 is about 448.3594469234.

The spelling of 90131993 in words is "ninety million, one hundred thirty-one thousand, nine hundred ninety-three".