91988997873 has 8 divisors (see below), whose sum is σ = 122660489088. Its totient is φ = 61321752624.

The previous prime is 91988997871. The next prime is 91988997931. The reversal of 91988997873 is 37879988919.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 91988997873 - 2¹ = 91988997871 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91988997871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1010590 + ... + 1097847.

It is an arithmetic number, because the mean of its divisors is an integer number (15332561136).

Almost surely, 2^91988997873 is an apocalyptic number.

It is an amenable number.

91988997873 is a deficient number, since it is larger than the sum of its proper divisors (30671491215).

91988997873 is a wasteful number, since it uses less digits than its factorization.

91988997873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2122983.

The product of its digits is 493807104, while the sum is 78.

The spelling of 91988997873 in words is "ninety-one billion, nine hundred eighty-eight million, nine hundred ninety-seven thousand, eight hundred seventy-three".