400020539 has 2 divisors, whose sum is σ = 400020540. Its totient is φ = 400020538.

The previous prime is 400020487. The next prime is 400020563. The reversal of 400020539 is 935020004.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400020539 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (400020589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200010269 + 200010270.

It is an arithmetic number, because the mean of its divisors is an integer number (200010270).

Almost surely, 2^400020539 is an apocalyptic number.

400020539 is a deficient number, since it is larger than the sum of its proper divisors (1).

400020539 is an equidigital number, since it uses as much as digits as its factorization.

400020539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 400020539 is about 20000.5134684088. The cubic root of 400020539 is about 736.8189105661.

The spelling of 400020539 in words is "four hundred million, twenty thousand, five hundred thirty-nine".