90120291994 has 4 divisors (see below), whose sum is σ = 135180437994. Its totient is φ = 45060145996.

The previous prime is 90120291991. The next prime is 90120292007. The reversal of 90120291994 is 49919202109.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49919202109 = 7 ⋅7131314587.

It can be written as a sum of positive squares in only one way, i.e., 64294194969 + 25826097025 = 253563^2 + 160705^2 .

It is not an unprimeable number, because it can be changed into a prime (90120291991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22530072997 + ... + 22530073000.

Almost surely, 2^90120291994 is an apocalyptic number.

90120291994 is a deficient number, since it is larger than the sum of its proper divisors (45060146000).

90120291994 is a wasteful number, since it uses less digits than its factorization.

90120291994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45060145999.

The product of its (nonzero) digits is 104976, while the sum is 46.

The spelling of 90120291994 in words is "ninety billion, one hundred twenty million, two hundred ninety-one thousand, nine hundred ninety-four".