921993 has 8 divisors (see below), whose sum is σ = 1250400. Its totient is φ = 604128.

The previous prime is 921989. The next prime is 922021. The reversal of 921993 is 399129.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 921993 - 2² = 921989 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (921913) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2428 + ... + 2781.

It is an arithmetic number, because the mean of its divisors is an integer number (156300).

2⁹²¹⁹⁹³ is an apocalyptic number.

It is an amenable number.

921993 is a deficient number, since it is larger than the sum of its proper divisors (328407).

921993 is a wasteful number, since it uses less digits than its factorization.

921993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5271.

The product of its digits is 4374, while the sum is 33.

The square root of 921993 is about 960.2046656833. The cubic root of 921993 is about 97.3290627492.

The spelling of 921993 in words is "nine hundred twenty-one thousand, nine hundred ninety-three".