20181339 has 8 divisors (see below), whose sum is σ = 29898320. Its totient is φ = 13454208.

The previous prime is 20181323. The next prime is 20181347. The reversal of 20181339 is 93318102.

It is not a de Polignac number, because 20181339 - 2⁴ = 20181323 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 747457 = 20181339 / (2 + 0 + 1 + 8 + 1 + 3 + 3 + 9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20181349) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 373702 + ... + 373755.

It is an arithmetic number, because the mean of its divisors is an integer number (3737290).

Almost surely, 2^20181339 is an apocalyptic number.

20181339 is a deficient number, since it is larger than the sum of its proper divisors (9716981).

20181339 is an equidigital number, since it uses as much as digits as its factorization.

20181339 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 747466 (or 747460 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 20181339 is about 4492.3645221642. The cubic root of 20181339 is about 272.2596775772.

The spelling of 20181339 in words is "twenty million, one hundred eighty-one thousand, three hundred thirty-nine".