91711047 has 4 divisors (see below), whose sum is σ = 122281400. Its totient is φ = 61140696.

The previous prime is 91711033. The next prime is 91711063. The reversal of 91711047 is 74011719.

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

It is not a de Polignac number, because 91711047 - 2⁸ = 91710791 is a prime.

It is a super-2 number, since 2×91711047² = 16821832283672418, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91711027) 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, 15285172 + ... + 15285177.

It is an arithmetic number, because the mean of its divisors is an integer number (30570350).

Almost surely, 2^91711047 is an apocalyptic number.

91711047 is a deficient number, since it is larger than the sum of its proper divisors (30570353).

91711047 is a wasteful number, since it uses less digits than its factorization.

91711047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30570352.

The product of its (nonzero) digits is 1764, while the sum is 30.

The square root of 91711047 is about 9576.5884844239. The cubic root of 91711047 is about 450.9626257330.

The spelling of 91711047 in words is "ninety-one million, seven hundred eleven thousand, forty-seven".