91868439 has 16 divisors (see below), whose sum is σ = 138857600. Its totient is φ = 53558496.

The previous prime is 91868437. The next prime is 91868443. The reversal of 91868439 is 93486819.

It is not a de Polignac number, because 91868439 - 2¹ = 91868437 is a prime.

It is a Smith number, since the sum of its digits (48) 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 a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91868431) 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, 61249 + ... + 62730.

It is an arithmetic number, because the mean of its divisors is an integer number (8678600).

Almost surely, 2^91868439 is an apocalyptic number.

91868439 is a deficient number, since it is larger than the sum of its proper divisors (46989161).

91868439 is a wasteful number, since it uses less digits than its factorization.

91868439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124014.

The product of its digits is 373248, while the sum is 48.

The square root of 91868439 is about 9584.8025018776. The cubic root of 91868439 is about 451.2204548863.

The spelling of 91868439 in words is "ninety-one million, eight hundred sixty-eight thousand, four hundred thirty-nine".