91666851 has 4 divisors (see below), whose sum is σ = 122222472. Its totient is φ = 61111232.

The previous prime is 91666829. The next prime is 91666859. The reversal of 91666851 is 15866619.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91666851 - 2¹³ = 91658659 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91666859) 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, 15277806 + ... + 15277811.

It is an arithmetic number, because the mean of its divisors is an integer number (30555618).

Almost surely, 2^91666851 is an apocalyptic number.

91666851 is a deficient number, since it is larger than the sum of its proper divisors (30555621).

91666851 is a wasteful number, since it uses less digits than its factorization.

91666851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30555620.

The product of its digits is 77760, while the sum is 42.

The square root of 91666851 is about 9574.2807040529. The cubic root of 91666851 is about 450.8901737319.

The spelling of 91666851 in words is "ninety-one million, six hundred sixty-six thousand, eight hundred fifty-one".