402140639 has 2 divisors, whose sum is σ = 402140640. Its totient is φ = 402140638.

The previous prime is 402140611. The next prime is 402140647. The reversal of 402140639 is 936041204.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 402140639 - 2¹⁶ = 402075103 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (402140689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201070319 + 201070320.

It is an arithmetic number, because the mean of its divisors is an integer number (201070320).

Almost surely, 2^402140639 is an apocalyptic number.

402140639 is a deficient number, since it is larger than the sum of its proper divisors (1).

402140639 is an equidigital number, since it uses as much as digits as its factorization.

402140639 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 402140639 is about 20053.4445669566. Note that the first 3 decimals coincide. The cubic root of 402140639 is about 738.1183256098.

The spelling of 402140639 in words is "four hundred two million, one hundred forty thousand, six hundred thirty-nine".