91870247 has 6 divisors (see below), whose sum is σ = 106869528. Its totient is φ = 78745884.

The previous prime is 91870213. The next prime is 91870279. The reversal of 91870247 is 74207819.

It is not a de Polignac number, because 91870247 - 2²⁶ = 24761383 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 91870247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91870447) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 937403 + ... + 937500.

It is an arithmetic number, because the mean of its divisors is an integer number (17811588).

Almost surely, 2^91870247 is an apocalyptic number.

91870247 is a deficient number, since it is larger than the sum of its proper divisors (14999281).

91870247 is a wasteful number, since it uses less digits than its factorization.

91870247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1874917 (or 1874910 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 91870247 is about 9584.8968173893. The cubic root of 91870247 is about 451.2234149208.

The spelling of 91870247 in words is "ninety-one million, eight hundred seventy thousand, two hundred forty-seven".