1663967 has 2 divisors, whose sum is σ = 1663968. Its totient is φ = 1663966.

The previous prime is 1663951. The next prime is 1663973. The reversal of 1663967 is 7693661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1663967 - 2⁴ = 1663951 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1663967.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1663997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831983 + 831984.

It is an arithmetic number, because the mean of its divisors is an integer number (831984).

2^1663967 is an apocalyptic number.

1663967 is a deficient number, since it is larger than the sum of its proper divisors (1).

1663967 is an equidigital number, since it uses as much as digits as its factorization.

1663967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 38.

The square root of 1663967 is about 1289.9484485823. The cubic root of 1663967 is about 118.4990593788.

The spelling of 1663967 in words is "one million, six hundred sixty-three thousand, nine hundred sixty-seven".