1388691 has 16 divisors (see below), whose sum is σ = 2166400. Its totient is φ = 876744.

The previous prime is 1388687. The next prime is 1388693. The reversal of 1388691 is 1968831.

It is not a de Polignac number, because 1388691 - 2² = 1388687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1388693) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 841 + ... + 1866.

It is an arithmetic number, because the mean of its divisors is an integer number (135400).

2^1388691 is an apocalyptic number.

1388691 is a deficient number, since it is larger than the sum of its proper divisors (777709).

1388691 is a wasteful number, since it uses less digits than its factorization.

1388691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2735 (or 2729 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 1388691 is about 1178.4273418417. The cubic root of 1388691 is about 111.5668591616.

The spelling of 1388691 in words is "one million, three hundred eighty-eight thousand, six hundred ninety-one".