438440467891 has 2 divisors, whose sum is σ = 438440467892. Its totient is φ = 438440467890.

The previous prime is 438440467859. The next prime is 438440467963. The reversal of 438440467891 is 198764044834.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 438440467891 - 2⁵ = 438440467859 is a prime.

It is not a weakly prime, because it can be changed into another prime (438440467811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 219220233945 + 219220233946.

It is an arithmetic number, because the mean of its divisors is an integer number (219220233946).

Almost surely, 2^438440467891 is an apocalyptic number.

438440467891 is a deficient number, since it is larger than the sum of its proper divisors (1).

438440467891 is an equidigital number, since it uses as much as digits as its factorization.

438440467891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18579456, while the sum is 58.

The spelling of 438440467891 in words is "four hundred thirty-eight billion, four hundred forty million, four hundred sixty-seven thousand, eight hundred ninety-one".