1340021839 has 4 divisors (see below), whose sum is σ = 1443100456. Its totient is φ = 1236943224.

The previous prime is 1340021807. The next prime is 1340021849. The reversal of 1340021839 is 9381200431.

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 1340021839 - 2⁵ = 1340021807 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1340021839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1340021849) 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, 51539289 + ... + 51539314.

It is an arithmetic number, because the mean of its divisors is an integer number (360775114).

Almost surely, 2^1340021839 is an apocalyptic number.

1340021839 is a deficient number, since it is larger than the sum of its proper divisors (103078617).

1340021839 is a wasteful number, since it uses less digits than its factorization.

1340021839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103078616.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 1340021839 is about 36606.3087322390. The cubic root of 1340021839 is about 1102.4797607019.

The spelling of 1340021839 in words is "one billion, three hundred forty million, twenty-one thousand, eight hundred thirty-nine".