91990250163 has 24 divisors (see below), whose sum is σ = 152155317600. Its totient is φ = 52462566144.

The previous prime is 91990250159. The next prime is 91990250173. The reversal of 91990250163 is 36105209919.

It is a happy number.

It is not a de Polignac number, because 91990250163 - 2² = 91990250159 is a prime.

It is a super-2 number, since 2×91990250163² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91990250123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1402278 + ... + 1466411.

It is an arithmetic number, because the mean of its divisors is an integer number (6339804900).

Almost surely, 2^91990250163 is an apocalyptic number.

91990250163 is a deficient number, since it is larger than the sum of its proper divisors (60165067437).

91990250163 is a wasteful number, since it uses less digits than its factorization.

91990250163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2869211 (or 2869208 counting only the distinct ones).

The product of its (nonzero) digits is 131220, while the sum is 45.

The spelling of 91990250163 in words is "ninety-one billion, nine hundred ninety million, two hundred fifty thousand, one hundred sixty-three".