671305657 has 4 divisors (see below), whose sum is σ = 732333456. Its totient is φ = 610277860.

The previous prime is 671305633. The next prime is 671305667. The reversal of 671305657 is 756503176.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-671305657 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (671305667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30513883 + ... + 30513904.

It is an arithmetic number, because the mean of its divisors is an integer number (183083364).

Almost surely, 2^671305657 is an apocalyptic number.

It is an amenable number.

671305657 is a deficient number, since it is larger than the sum of its proper divisors (61027799).

671305657 is a wasteful number, since it uses less digits than its factorization.

671305657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61027798.

The product of its (nonzero) digits is 132300, while the sum is 40.

The square root of 671305657 is about 25909.5669010503. The cubic root of 671305657 is about 875.6020485737.

The spelling of 671305657 in words is "six hundred seventy-one million, three hundred five thousand, six hundred fifty-seven".