7905921 has 8 divisors (see below), whose sum is σ = 10689984. Its totient is φ = 5196240.

The previous prime is 7905889. The next prime is 7905929. The reversal of 7905921 is 1295097.

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

It is not a de Polignac number, because 7905921 - 2⁵ = 7905889 is a prime.

7905921 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (7905929) 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, 18346 + ... + 18771.

It is an arithmetic number, because the mean of its divisors is an integer number (1336248).

Almost surely, 2^7905921 is an apocalyptic number.

7905921 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

7905921 is a deficient number, since it is larger than the sum of its proper divisors (2784063).

7905921 is a wasteful number, since it uses less digits than its factorization.

7905921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37191.

The product of its (nonzero) digits is 5670, while the sum is 33.

The square root of 7905921 is about 2811.7469658559. The cubic root of 7905921 is about 199.2129148818.

The spelling of 7905921 in words is "seven million, nine hundred five thousand, nine hundred twenty-one".