1669979 has 2 divisors, whose sum is σ = 1669980. Its totient is φ = 1669978.

The previous prime is 1669963. The next prime is 1669999. The reversal of 1669979 is 9799661.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (9799661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1669979 - 2⁴ = 1669963 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1669999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834989 + 834990.

It is an arithmetic number, because the mean of its divisors is an integer number (834990).

2^1669979 is an apocalyptic number.

1669979 is a deficient number, since it is larger than the sum of its proper divisors (1).

1669979 is an equidigital number, since it uses as much as digits as its factorization.

1669979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 183708, while the sum is 47.

The square root of 1669979 is about 1292.2766731625. The cubic root of 1669979 is about 118.6416022826.

The spelling of 1669979 in words is "one million, six hundred sixty-nine thousand, nine hundred seventy-nine".