1392139281 has 8 divisors (see below), whose sum is σ = 1998969280. Its totient is φ = 856701072.

The previous prime is 1392139277. The next prime is 1392139283. The reversal of 1392139281 is 1829312931.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1392139281 - 2² = 1392139277 is a prime.

It is a super-2 number, since 2×1392139281² = 3876103555406393922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 35695879 = 1392139281 / (1 + 3 + 9 + 2 + 1 + 3 + 9 + 2 + 8 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1392139283) 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, 17847901 + ... + 17847978.

It is an arithmetic number, because the mean of its divisors is an integer number (249871160).

Almost surely, 2^1392139281 is an apocalyptic number.

It is an amenable number.

1392139281 is a deficient number, since it is larger than the sum of its proper divisors (606829999).

1392139281 is a wasteful number, since it uses less digits than its factorization.

1392139281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35695895.

The product of its digits is 23328, while the sum is 39.

The square root of 1392139281 is about 37311.3827269910. The cubic root of 1392139281 is about 1116.5912732148.

The spelling of 1392139281 in words is "one billion, three hundred ninety-two million, one hundred thirty-nine thousand, two hundred eighty-one".