1660739 has 2 divisors, whose sum is σ = 1660740. Its totient is φ = 1660738.

The previous prime is 1660727. The next prime is 1660741. The reversal of 1660739 is 9370661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1660739 - 2⁴ = 1660723 is a prime.

It is a super-2 number, since 2×1660739² = 5516108052242, which contains 22 as substring.

Together with 1660741, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1660709) 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 as a sum of consecutive naturals, namely, 830369 + 830370.

It is an arithmetic number, because the mean of its divisors is an integer number (830370).

2^1660739 is an apocalyptic number.

1660739 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660739 is an equidigital number, since it uses as much as digits as its factorization.

1660739 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6804, while the sum is 32.

The square root of 1660739 is about 1288.6966283808. The cubic root of 1660739 is about 118.4223826613.

The spelling of 1660739 in words is "one million, six hundred sixty thousand, seven hundred thirty-nine".