4086921 has 16 divisors (see below), whose sum is σ = 5644800. Its totient is φ = 2628480.

The previous prime is 4086913. The next prime is 4086923. The reversal of 4086921 is 1296804.

It is not a de Polignac number, because 4086921 - 2³ = 4086913 is a prime.

4086921 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (4086923) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18216 + ... + 18438.

It is an arithmetic number, because the mean of its divisors is an integer number (352800).

Almost surely, 2^4086921 is an apocalyptic number.

4086921 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

4086921 is a deficient number, since it is larger than the sum of its proper divisors (1557879).

4086921 is a wasteful number, since it uses less digits than its factorization.

4086921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 4086921 is about 2021.6134645377. The cubic root of 4086921 is about 159.8816964023.

The spelling of 4086921 in words is "four million, eighty-six thousand, nine hundred twenty-one".