91885421 has 4 divisors (see below), whose sum is σ = 91947744. Its totient is φ = 91823100.

The previous prime is 91885397. The next prime is 91885429. The reversal of 91885421 is 12458819.

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: 12458819 = 929 ⋅13411.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91885421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91885429) 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, 28895 + ... + 31916.

It is an arithmetic number, because the mean of its divisors is an integer number (22986936).

Almost surely, 2^91885421 is an apocalyptic number.

It is an amenable number.

91885421 is a deficient number, since it is larger than the sum of its proper divisors (62323).

91885421 is a wasteful number, since it uses less digits than its factorization.

91885421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62322.

The product of its digits is 23040, while the sum is 38.

The square root of 91885421 is about 9585.6883425240. The cubic root of 91885421 is about 451.2482560686.

The spelling of 91885421 in words is "ninety-one million, eight hundred eighty-five thousand, four hundred twenty-one".