90179071987 has 4 divisors (see below), whose sum is σ = 90183792160. Its totient is φ = 90174351816.

The previous prime is 90179071909. The next prime is 90179072021. The reversal of 90179071987 is 78917097109.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78917097109 = 9623 ⋅8200883.

It is a cyclic number.

It is not a de Polignac number, because 90179071987 - 2⁷ = 90179071859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90179071907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2331312 + ... + 2369677.

It is an arithmetic number, because the mean of its divisors is an integer number (22545948040).

Almost surely, 2^90179071987 is an apocalyptic number.

90179071987 is a deficient number, since it is larger than the sum of its proper divisors (4720173).

90179071987 is a wasteful number, since it uses less digits than its factorization.

90179071987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4720172.

The product of its (nonzero) digits is 2000376, while the sum is 58.

The spelling of 90179071987 in words is "ninety billion, one hundred seventy-nine million, seventy-one thousand, nine hundred eighty-seven".