673645864 has 8 divisors (see below), whose sum is σ = 1263086010. Its totient is φ = 336822928.

The previous prime is 673645829. The next prime is 673645883. The reversal of 673645864 is 468546376.

It can be written as a sum of positive squares in only one way, i.e., 652393764 + 21252100 = 25542^2 + 4610^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42102859 + ... + 42102874.

Almost surely, 2^673645864 is an apocalyptic number.

It is an amenable number.

673645864 is a deficient number, since it is larger than the sum of its proper divisors (589440146).

673645864 is a wasteful number, since it uses less digits than its factorization.

673645864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84205739 (or 84205735 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 49.

The square root of 673645864 is about 25954.6886708356. The cubic root of 673645864 is about 876.6183335521.

The spelling of 673645864 in words is "six hundred seventy-three million, six hundred forty-five thousand, eight hundred sixty-four".