649587671 has 4 divisors (see below), whose sum is σ = 670542144. Its totient is φ = 628633200.

The previous prime is 649587613. The next prime is 649587709. The reversal of 649587671 is 176785946.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-649587671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649547671) 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, 10477190 + ... + 10477251.

It is an arithmetic number, because the mean of its divisors is an integer number (167635536).

Almost surely, 2^649587671 is an apocalyptic number.

649587671 is a deficient number, since it is larger than the sum of its proper divisors (20954473).

649587671 is a wasteful number, since it uses less digits than its factorization.

649587671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20954472.

The product of its digits is 2540160, while the sum is 53.

The square root of 649587671 is about 25487.0098481560. The cubic root of 649587671 is about 866.0558996713.

The spelling of 649587671 in words is "six hundred forty-nine million, five hundred eighty-seven thousand, six hundred seventy-one".