91874809 has 8 divisors (see below), whose sum is σ = 101355912. Its totient is φ = 82738560.

The previous prime is 91874791. The next prime is 91874821. The reversal of 91874809 is 90847819.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1092025 + 90782784 = 1045^2 + 9528^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91874809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91874869) 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, 85654 + ... + 86719.

It is an arithmetic number, because the mean of its divisors is an integer number (12669489).

Almost surely, 2^91874809 is an apocalyptic number.

It is an amenable number.

91874809 is a deficient number, since it is larger than the sum of its proper divisors (9481103).

91874809 is a wasteful number, since it uses less digits than its factorization.

91874809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172427.

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 91874809 is about 9585.1347930011. The cubic root of 91874809 is about 451.2308835961.

The spelling of 91874809 in words is "ninety-one million, eight hundred seventy-four thousand, eight hundred nine".