1338808891 has 4 divisors (see below), whose sum is σ = 1530067312. Its totient is φ = 1147550472.

The previous prime is 1338808859. The next prime is 1338808901. The reversal of 1338808891 is 1988088331.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1338808891 - 2⁵ = 1338808859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1338808591) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 95629200 + ... + 95629213.

It is an arithmetic number, because the mean of its divisors is an integer number (382516828).

Almost surely, 2^1338808891 is an apocalyptic number.

1338808891 is a deficient number, since it is larger than the sum of its proper divisors (191258421).

1338808891 is an equidigital number, since it uses as much as digits as its factorization.

1338808891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191258420.

The product of its (nonzero) digits is 331776, while the sum is 49.

The square root of 1338808891 is about 36589.7375093072. The cubic root of 1338808891 is about 1102.1470162982.

It can be divided in two parts, 133 and 8808891, that added together give a square (8809024 = 2968²).

The spelling of 1338808891 in words is "one billion, three hundred thirty-eight million, eight hundred eight thousand, eight hundred ninety-one".