1387999279 has 8 divisors (see below), whose sum is σ = 1428998912. Its totient is φ = 1347396120.

The previous prime is 1387999259. The next prime is 1387999309. The reversal of 1387999279 is 9729997831.

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

It is a cyclic number.

It is not a de Polignac number, because 1387999279 - 2⁹ = 1387998767 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 1387999279.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1387999259) 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, 92007 + ... + 106024.

It is an arithmetic number, because the mean of its divisors is an integer number (178624864).

Almost surely, 2^1387999279 is an apocalyptic number.

1387999279 is a deficient number, since it is larger than the sum of its proper divisors (40999633).

1387999279 is a wasteful number, since it uses less digits than its factorization.

1387999279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198237.

The product of its digits is 15431472, while the sum is 64.

The square root of 1387999279 is about 37255.8623440661. The cubic root of 1387999279 is about 1115.4833189231.

The spelling of 1387999279 in words is "one billion, three hundred eighty-seven million, nine hundred ninety-nine thousand, two hundred seventy-nine".