10091921 has 4 divisors (see below), whose sum is σ = 11533632. Its totient is φ = 8650212.

The previous prime is 10091911. The next prime is 10091923. The reversal of 10091921 is 12919001.

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 a cyclic number.

It is not a de Polignac number, because 10091921 - 2¹⁰ = 10090897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (10091923) 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, 720845 + ... + 720858.

It is an arithmetic number, because the mean of its divisors is an integer number (2883408).

Almost surely, 2^10091921 is an apocalyptic number.

It is an amenable number.

10091921 is a deficient number, since it is larger than the sum of its proper divisors (1441711).

10091921 is an equidigital number, since it uses as much as digits as its factorization.

10091921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1441710.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 10091921 is about 3176.7783995740. The cubic root of 10091921 is about 216.1015825919.

The spelling of 10091921 in words is "ten million, ninety-one thousand, nine hundred twenty-one".