1383991 has 4 divisors (see below), whose sum is σ = 1581712. Its totient is φ = 1186272.

The previous prime is 1383983. The next prime is 1384013. The reversal of 1383991 is 1993831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1993831 = 7 ⋅284833.

It is a cyclic number.

It is not a de Polignac number, because 1383991 - 2³ = 1383983 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 (1383901) 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, 98850 + ... + 98863.

It is an arithmetic number, because the mean of its divisors is an integer number (395428).

2^1383991 is an apocalyptic number.

1383991 is a deficient number, since it is larger than the sum of its proper divisors (197721).

1383991 is an equidigital number, since it uses as much as digits as its factorization.

1383991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197720.

The product of its digits is 5832, while the sum is 34.

The square root of 1383991 is about 1176.4314684672. The cubic root of 1383991 is about 111.4408515473.

The spelling of 1383991 in words is "one million, three hundred eighty-three thousand, nine hundred ninety-one".