671749731 has 12 divisors (see below), whose sum is σ = 1021374120. Its totient is φ = 424262880.

The previous prime is 671749717. The next prime is 671749783. The reversal of 671749731 is 137947176.

It is a happy number.

It is not a de Polignac number, because 671749731 - 2⁶ = 671749667 is a prime.

It is a super-2 number, since 2×671749731² = 902495402197144722, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (671749711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1964010 + ... + 1964351.

It is an arithmetic number, because the mean of its divisors is an integer number (85114510).

Almost surely, 2^671749731 is an apocalyptic number.

671749731 is a deficient number, since it is larger than the sum of its proper divisors (349624389).

671749731 is a wasteful number, since it uses less digits than its factorization.

671749731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3928386 (or 3928383 counting only the distinct ones).

The product of its digits is 222264, while the sum is 45.

The square root of 671749731 is about 25918.1351759728. The cubic root of 671749731 is about 875.7950785758.

The spelling of 671749731 in words is "six hundred seventy-one million, seven hundred forty-nine thousand, seven hundred thirty-one".