91601982851 has 4 divisors (see below), whose sum is σ = 91602675000. Its totient is φ = 91601290704.

The previous prime is 91601982841. The next prime is 91601982877. The reversal of 91601982851 is 15828910619.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 15828910619 = 34337 ⋅460987.

It is a cyclic number.

It is not a de Polignac number, because 91601982851 - 2²⁶ = 91534873987 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91601982851.

It is not an unprimeable number, because it can be changed into a prime (91601982811) 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, 78701 + ... + 435198.

It is an arithmetic number, because the mean of its divisors is an integer number (22900668750).

Almost surely, 2^91601982851 is an apocalyptic number.

91601982851 is a deficient number, since it is larger than the sum of its proper divisors (692149).

91601982851 is a wasteful number, since it uses less digits than its factorization.

91601982851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 692148.

The product of its (nonzero) digits is 311040, while the sum is 50.

The spelling of 91601982851 in words is "ninety-one billion, six hundred one million, nine hundred eighty-two thousand, eight hundred fifty-one".