1399690 has 8 divisors (see below), whose sum is σ = 2519460. Its totient is φ = 559872.

The previous prime is 1399687. The next prime is 1399691. The reversal of 1399690 is 969931.

It can be written as a sum of positive squares in 2 ways, for example, as 1212201 + 187489 = 1101^2 + 433^2 .

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

It is a super-2 number, since 2×1399690² = 3918264192200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1399691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69975 + ... + 69994.

2^1399690 is an apocalyptic number.

1399690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1399690 is a deficient number, since it is larger than the sum of its proper divisors (1119770).

1399690 is a wasteful number, since it uses less digits than its factorization.

1399690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139976.

The product of its (nonzero) digits is 13122, while the sum is 37.

The square root of 1399690 is about 1183.0849504579. The cubic root of 1399690 is about 111.8606366088.

The spelling of 1399690 in words is "one million, three hundred ninety-nine thousand, six hundred ninety".