400004239 has 2 divisors, whose sum is σ = 400004240. Its totient is φ = 400004238.

The previous prime is 400004219. The next prime is 400004249. The reversal of 400004239 is 932400004.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 400004239 - 2²⁷ = 265786511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400004219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200002119 + 200002120.

It is an arithmetic number, because the mean of its divisors is an integer number (200002120).

Almost surely, 2^400004239 is an apocalyptic number.

400004239 is a deficient number, since it is larger than the sum of its proper divisors (1).

400004239 is an equidigital number, since it uses as much as digits as its factorization.

400004239 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 400004239 is about 20000.1059747192. The cubic root of 400004239 is about 736.8089024871.

The spelling of 400004239 in words is "four hundred million, four thousand, two hundred thirty-nine".