1438833891 has 16 divisors (see below), whose sum is σ = 2095008768. Its totient is φ = 871120800.

The previous prime is 1438833871. The next prime is 1438833917. The reversal of 1438833891 is 1983388341.

It is not a de Polignac number, because 1438833891 - 2¹⁸ = 1438571747 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1438833891.

It is not an unprimeable number, because it can be changed into a prime (1438833871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10705 + ... + 54701.

It is an arithmetic number, because the mean of its divisors is an integer number (130938048).

Almost surely, 2^1438833891 is an apocalyptic number.

1438833891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1438833891 is a deficient number, since it is larger than the sum of its proper divisors (656174877).

1438833891 is a wasteful number, since it uses less digits than its factorization.

1438833891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45002.

The product of its digits is 497664, while the sum is 48.

The square root of 1438833891 is about 37931.9639749908. The cubic root of 1438833891 is about 1128.9383327332.

The spelling of 1438833891 in words is "one billion, four hundred thirty-eight million, eight hundred thirty-three thousand, eight hundred ninety-one".