1673981 has 2 divisors, whose sum is σ = 1673982. Its totient is φ = 1673980.

The previous prime is 1673953. The next prime is 1673983. The reversal of 1673981 is 1893761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1301881 + 372100 = 1141^2 + 610^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1673981 is a prime.

It is a super-2 number, since 2×1673981² = 5604424776722, which contains 22 as substring.

Together with 1673983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1673983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 836990 + 836991.

It is an arithmetic number, because the mean of its divisors is an integer number (836991).

2^1673981 is an apocalyptic number.

It is an amenable number.

1673981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1673981 is an equidigital number, since it uses as much as digits as its factorization.

1673981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 35.

The square root of 1673981 is about 1293.8241766175. The cubic root of 1673981 is about 118.7362990657.

The spelling of 1673981 in words is "one million, six hundred seventy-three thousand, nine hundred eighty-one".