90918201091 has 4 divisors (see below), whose sum is σ = 90937661832. Its totient is φ = 90898740352.

The previous prime is 90918201089. The next prime is 90918201137. The reversal of 90918201091 is 19010281909.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19010281909 = 17 ⋅1118251877.

It is a cyclic number.

It is not a de Polignac number, because 90918201091 - 2¹ = 90918201089 is a prime.

It is a super-2 number, since 2×90918201091² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90918201061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9723361 + ... + 9732706.

It is an arithmetic number, because the mean of its divisors is an integer number (22734415458).

Almost surely, 2^90918201091 is an apocalyptic number.

90918201091 is a deficient number, since it is larger than the sum of its proper divisors (19460741).

90918201091 is a wasteful number, since it uses less digits than its factorization.

90918201091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19460740.

The product of its (nonzero) digits is 11664, while the sum is 40.

The spelling of 90918201091 in words is "ninety billion, nine hundred eighteen million, two hundred one thousand, ninety-one".