91670431 has 4 divisors (see below), whose sum is σ = 92527272. Its totient is φ = 90813592.

The previous prime is 91670419. The next prime is 91670461. The reversal of 91670431 is 13407619.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13407619 = 1063 ⋅12613.

It is a cyclic number.

It is not a de Polignac number, because 91670431 - 2¹¹ = 91668383 is a prime.

It is a super-2 number, since 2×91670431² = 16806935839451522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91670393 and 91670402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91670461) 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, 428260 + ... + 428473.

It is an arithmetic number, because the mean of its divisors is an integer number (23131818).

Almost surely, 2^91670431 is an apocalyptic number.

91670431 is a deficient number, since it is larger than the sum of its proper divisors (856841).

91670431 is a wasteful number, since it uses less digits than its factorization.

91670431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 856840.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 91670431 is about 9574.4676614421. The cubic root of 91670431 is about 450.8960434139.

The spelling of 91670431 in words is "ninety-one million, six hundred seventy thousand, four hundred thirty-one".