1399386991 has 8 divisors (see below), whose sum is σ = 1429815600. Its totient is φ = 1369239168.

The previous prime is 1399386983. The next prime is 1399387007. The reversal of 1399386991 is 1996839931.

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 1399386991 - 2³ = 1399386983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1399386091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60106 + ... + 80071.

It is an arithmetic number, because the mean of its divisors is an integer number (178726950).

Almost surely, 2^1399386991 is an apocalyptic number.

1399386991 is a deficient number, since it is larger than the sum of its proper divisors (30428609).

1399386991 is a wasteful number, since it uses less digits than its factorization.

1399386991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140393.

The product of its digits is 2834352, while the sum is 58.

The square root of 1399386991 is about 37408.3812935016. The cubic root of 1399386991 is about 1118.5256405326.

The spelling of 1399386991 in words is "one billion, three hundred ninety-nine million, three hundred eighty-six thousand, nine hundred ninety-one".