90191001 has 32 divisors (see below), whose sum is σ = 132098688. Its totient is φ = 54512640.

The previous prime is 90190993. The next prime is 90191029. The reversal of 90191001 is 10019109.

It is not a de Polignac number, because 90191001 - 2³ = 90190993 is a prime.

It is a super-2 number, since 2×90191001² = 16268833322764002, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (90191201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 164610 + ... + 165156.

It is an arithmetic number, because the mean of its divisors is an integer number (4128084).

Almost surely, 2^90191001 is an apocalyptic number.

It is an amenable number.

90191001 is a deficient number, since it is larger than the sum of its proper divisors (41907687).

90191001 is a wasteful number, since it uses less digits than its factorization.

90191001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681.

The product of its (nonzero) digits is 81, while the sum is 21.

The square root of 90191001 is about 9496.8942818166. The cubic root of 90191001 is about 448.4572702077.

The spelling of 90191001 in words is "ninety million, one hundred ninety-one thousand, one".