4020399 has 12 divisors (see below), whose sum is σ = 5864976. Its totient is φ = 2653632.

The previous prime is 4020361. The next prime is 4020407. The reversal of 4020399 is 9930204.

It is not a de Polignac number, because 4020399 - 2¹³ = 4012207 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

4020399 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4020349) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1242 + ... + 3095.

It is an arithmetic number, because the mean of its divisors is an integer number (488748).

Almost surely, 2^4020399 is an apocalyptic number.

4020399 is a deficient number, since it is larger than the sum of its proper divisors (1844577).

4020399 is a wasteful number, since it uses less digits than its factorization.

4020399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4446 (or 4443 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 4020399 is about 2005.0932646638. The cubic root of 4020399 is about 159.0094927286.

The spelling of 4020399 in words is "four million, twenty thousand, three hundred ninety-nine".