400239641 has 2 divisors, whose sum is σ = 400239642. Its totient is φ = 400239640.

The previous prime is 400239613. The next prime is 400239647. The reversal of 400239641 is 146932004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 368486416 + 31753225 = 19196^2 + 5635^2 .

It is a cyclic number.

It is not a de Polignac number, because 400239641 - 2¹⁸ = 399977497 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (400239647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200119820 + 200119821.

It is an arithmetic number, because the mean of its divisors is an integer number (200119821).

Almost surely, 2^400239641 is an apocalyptic number.

It is an amenable number.

400239641 is a deficient number, since it is larger than the sum of its proper divisors (1).

400239641 is an equidigital number, since it uses as much as digits as its factorization.

400239641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 400239641 is about 20005.9901279592. The cubic root of 400239641 is about 736.9534111858.

The spelling of 400239641 in words is "four hundred million, two hundred thirty-nine thousand, six hundred forty-one".