671721730 has 16 divisors (see below), whose sum is σ = 1211069880. Its totient is φ = 268250752.

The previous prime is 671721727. The next prime is 671721761. The reversal of 671721730 is 37127176.

It can be written as a sum of positive squares in 4 ways, for example, as 374538609 + 297183121 = 19353^2 + 17239^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48265 + ... + 60604.

Almost surely, 2^671721730 is an apocalyptic number.

671721730 is a deficient number, since it is larger than the sum of its proper divisors (539348150).

671721730 is a wasteful number, since it uses less digits than its factorization.

671721730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109493.

The product of its (nonzero) digits is 12348, while the sum is 34.

The square root of 671721730 is about 25917.5949887330. The cubic root of 671721730 is about 875.7829096198.

The spelling of 671721730 in words is "six hundred seventy-one million, seven hundred twenty-one thousand, seven hundred thirty".