438694391 has 2 divisors, whose sum is σ = 438694392. Its totient is φ = 438694390.

The previous prime is 438694379. The next prime is 438694427. The reversal of 438694391 is 193496834.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 438694391 - 2⁶ = 438694327 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 (438694351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 219347195 + 219347196.

It is an arithmetic number, because the mean of its divisors is an integer number (219347196).

Almost surely, 2^438694391 is an apocalyptic number.

438694391 is a deficient number, since it is larger than the sum of its proper divisors (1).

438694391 is an equidigital number, since it uses as much as digits as its factorization.

438694391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 559872, while the sum is 47.

The square root of 438694391 is about 20945.0326091892. The cubic root of 438694391 is about 759.8374484995.

The spelling of 438694391 in words is "four hundred thirty-eight million, six hundred ninety-four thousand, three hundred ninety-one".