3940399 has 4 divisors (see below), whose sum is σ = 3960400. Its totient is φ = 3920400.

The previous prime is 3940397. The next prime is 3940411. The reversal of 3940399 is 9930493.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9930493 = 1427 ⋅6959.

It is a cyclic number.

It is not a de Polignac number, because 3940399 - 2¹ = 3940397 is a prime.

It is a Duffinian number.

3940399 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3940397) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9702 + ... + 10099.

It is an arithmetic number, because the mean of its divisors is an integer number (990100).

It is the magic constant of a 199 × 199 magic square.

Almost surely, 2^3940399 is an apocalyptic number.

3940399 is a deficient number, since it is larger than the sum of its proper divisors (20001).

3940399 is a wasteful number, since it uses less digits than its factorization.

3940399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20000.

The product of its (nonzero) digits is 26244, while the sum is 37.

The square root of 3940399 is about 1985.0438282315. The cubic root of 3940399 is about 157.9477341413.

The spelling of 3940399 in words is "three million, nine hundred forty thousand, three hundred ninety-nine".