1662979 has 2 divisors, whose sum is σ = 1662980. Its totient is φ = 1662978.

The previous prime is 1662977. The next prime is 1663009. The reversal of 1662979 is 9792661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1662979 - 2¹ = 1662977 is a prime.

Together with 1662977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1662977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831489 + 831490.

It is an arithmetic number, because the mean of its divisors is an integer number (831490).

2^1662979 is an apocalyptic number.

1662979 is a deficient number, since it is larger than the sum of its proper divisors (1).

1662979 is an equidigital number, since it uses as much as digits as its factorization.

1662979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 40.

The square root of 1662979 is about 1289.5654306781. The cubic root of 1662979 is about 118.4756013314.

The spelling of 1662979 in words is "one million, six hundred sixty-two thousand, nine hundred seventy-nine".