1399990 has 8 divisors (see below), whose sum is σ = 2520000. Its totient is φ = 559992.

The previous prime is 1399963. The next prime is 1399999. The reversal of 1399990 is 999931.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1399999) 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, 69990 + ... + 70009.

It is an arithmetic number, because the mean of its divisors is an integer number (315000).

2^1399990 is an apocalyptic number.

1399990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1399990 is a deficient number, since it is larger than the sum of its proper divisors (1120010).

1399990 is a wasteful number, since it uses less digits than its factorization.

1399990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140006.

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

The square root of 1399990 is about 1183.2117308411. The cubic root of 1399990 is about 111.8686278530.

The spelling of 1399990 in words is "one million, three hundred ninety-nine thousand, nine hundred ninety".