4005309 has 24 divisors (see below), whose sum is σ = 6779808. Its totient is φ = 2079840.

The previous prime is 4005307. The next prime is 4005317. The reversal of 4005309 is 9035004.

It is not a de Polignac number, because 4005309 - 2¹ = 4005307 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4005301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 379 + ... + 2855.

It is an arithmetic number, because the mean of its divisors is an integer number (282492).

Almost surely, 2^4005309 is an apocalyptic number.

4005309 is a gapful number since it is divisible by the number (49) formed by its first and last digit.

It is an amenable number.

4005309 is a deficient number, since it is larger than the sum of its proper divisors (2774499).

4005309 is a wasteful number, since it uses less digits than its factorization.

4005309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2505 (or 2498 counting only the distinct ones).

The product of its (nonzero) digits is 540, while the sum is 21.

The square root of 4005309 is about 2001.3268098939. The cubic root of 4005309 is about 158.8103034173.

The spelling of 4005309 in words is "four million, five thousand, three hundred nine".