91881473 has 4 divisors (see below), whose sum is σ = 96717360. Its totient is φ = 87045588.

The previous prime is 91881443. The next prime is 91881487. The reversal of 91881473 is 37418819.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 37418819 = 17 ⋅2201107.

It is a cyclic number.

It is not a de Polignac number, because 91881473 - 2⁶ = 91881409 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 91881473.

It is not an unprimeable number, because it can be changed into a prime (91881403) 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, 2417915 + ... + 2417952.

It is an arithmetic number, because the mean of its divisors is an integer number (24179340).

It is a Proth number, since it is equal to 701 ⋅ 2¹⁷ + 1 and 701 < 2¹⁷.

Almost surely, 2^91881473 is an apocalyptic number.

It is an amenable number.

91881473 is a deficient number, since it is larger than the sum of its proper divisors (4835887).

91881473 is a wasteful number, since it uses less digits than its factorization.

91881473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4835886.

The product of its digits is 48384, while the sum is 41.

The square root of 91881473 is about 9585.4824083089. The cubic root of 91881473 is about 451.2417931151.

The spelling of 91881473 in words is "ninety-one million, eight hundred eighty-one thousand, four hundred seventy-three".