91472639 has 4 divisors (see below), whose sum is σ = 92193024. Its totient is φ = 90752256.

The previous prime is 91472609. The next prime is 91472651. The reversal of 91472639 is 93627419.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93627419 = 2521 ⋅37139.

It is a cyclic number.

It is not a de Polignac number, because 91472639 - 2¹² = 91468543 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91472596 and 91472605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91472609) 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, 360002 + ... + 360255.

It is an arithmetic number, because the mean of its divisors is an integer number (23048256).

Almost surely, 2^91472639 is an apocalyptic number.

91472639 is a deficient number, since it is larger than the sum of its proper divisors (720385).

91472639 is a wasteful number, since it uses less digits than its factorization.

91472639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 720384.

The product of its digits is 81648, while the sum is 41.

The square root of 91472639 is about 9564.1329455419. The cubic root of 91472639 is about 450.5715191067.

The spelling of 91472639 in words is "ninety-one million, four hundred seventy-two thousand, six hundred thirty-nine".