91647491 has 16 divisors (see below), whose sum is σ = 102541824. Its totient is φ = 81363744.

The previous prime is 91647461. The next prime is 91647497. The reversal of 91647491 is 19474619.

It is a cyclic number.

It is not a de Polignac number, because 91647491 - 2²² = 87453187 is a prime.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91647497) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36230 + ... + 38676.

It is an arithmetic number, because the mean of its divisors is an integer number (6408864).

Almost surely, 2^91647491 is an apocalyptic number.

91647491 is a deficient number, since it is larger than the sum of its proper divisors (10894333).

91647491 is a wasteful number, since it uses less digits than its factorization.

91647491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2570.

The product of its digits is 54432, while the sum is 41.

The square root of 91647491 is about 9573.2696086551. The cubic root of 91647491 is about 450.8584288925.

The spelling of 91647491 in words is "ninety-one million, six hundred forty-seven thousand, four hundred ninety-one".