1673865643 has 2 divisors, whose sum is σ = 1673865644. Its totient is φ = 1673865642.

The previous prime is 1673865619. The next prime is 1673865671. The reversal of 1673865643 is 3465683761.

It is a weak prime.

It is an emirp because it is prime and its reverse (3465683761) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1673865643 is a prime.

It is not a weakly prime, because it can be changed into another prime (1673865443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 836932821 + 836932822.

It is an arithmetic number, because the mean of its divisors is an integer number (836932822).

Almost surely, 2^1673865643 is an apocalyptic number.

1673865643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1673865643 is an equidigital number, since it uses as much as digits as its factorization.

1673865643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2177280, while the sum is 49.

The square root of 1673865643 is about 40912.9031358079. The cubic root of 1673865643 is about 1187.3357156000.

The spelling of 1673865643 in words is "one billion, six hundred seventy-three million, eight hundred sixty-five thousand, six hundred forty-three".