1390999 has 4 divisors (see below), whose sum is σ = 1396440. Its totient is φ = 1385560.

The previous prime is 1390993. The next prime is 1391011. The reversal of 1390999 is 9990931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9990931 = 47 ⋅212573.

It is a cyclic number.

It is not a de Polignac number, because 1390999 - 2⁵ = 1390967 is a prime.

It is a Duffinian number.

1390999 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1390993) 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, 2317 + ... + 2854.

It is an arithmetic number, because the mean of its divisors is an integer number (349110).

2^1390999 is an apocalyptic number.

1390999 is a deficient number, since it is larger than the sum of its proper divisors (5441).

1390999 is an equidigital number, since it uses as much as digits as its factorization.

1390999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5440.

The product of its (nonzero) digits is 19683, while the sum is 40.

The square root of 1390999 is about 1179.4062065294. The cubic root of 1390999 is about 111.6286328727.

The spelling of 1390999 in words is "one million, three hundred ninety thousand, nine hundred ninety-nine".