91897473 has 4 divisors (see below), whose sum is σ = 122529968. Its totient is φ = 61264980.

The previous prime is 91897469. The next prime is 91897499. The reversal of 91897473 is 37479819.

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.

It is not a de Polignac number, because 91897473 - 2² = 91897469 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91897453) 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, 15316243 + ... + 15316248.

It is an arithmetic number, because the mean of its divisors is an integer number (30632492).

Almost surely, 2^91897473 is an apocalyptic number.

It is an amenable number.

91897473 is a deficient number, since it is larger than the sum of its proper divisors (30632495).

91897473 is a wasteful number, since it uses less digits than its factorization.

91897473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30632494.

The product of its digits is 381024, while the sum is 48.

The square root of 91897473 is about 9586.3169674281. The cubic root of 91897473 is about 451.2679842844.

The spelling of 91897473 in words is "ninety-one million, eight hundred ninety-seven thousand, four hundred seventy-three".