91712919 has 4 divisors (see below), whose sum is σ = 122283896. Its totient is φ = 61141944.

The previous prime is 91712903. The next prime is 91712939. The reversal of 91712919 is 91921719.

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

It is not a de Polignac number, because 91712919 - 2⁴ = 91712903 is a prime.

It is a super-2 number, since 2×91712919² = 16822519023001122, 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 (91712939) 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, 15285484 + ... + 15285489.

It is an arithmetic number, because the mean of its divisors is an integer number (30570974).

Almost surely, 2^91712919 is an apocalyptic number.

91712919 is a deficient number, since it is larger than the sum of its proper divisors (30570977).

91712919 is a wasteful number, since it uses less digits than its factorization.

91712919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30570976.

The product of its digits is 10206, while the sum is 39.

The square root of 91712919 is about 9576.6862222796. The cubic root of 91712919 is about 450.9656940521.

It can be divided in two parts, 9171 and 2919, that added together give a triangular number (12090 = T₁₅₅).

The spelling of 91712919 in words is "ninety-one million, seven hundred twelve thousand, nine hundred nineteen".