649977865 has 8 divisors (see below), whose sum is σ = 781342848. Its totient is φ = 519069360.

The previous prime is 649977773. The next prime is 649977869. The reversal of 649977865 is 568779946.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 649977865 - 2⁷ = 649977737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (649977869) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 110977 + ... + 116686.

It is an arithmetic number, because the mean of its divisors is an integer number (97667856).

Almost surely, 2^649977865 is an apocalyptic number.

It is an amenable number.

649977865 is a deficient number, since it is larger than the sum of its proper divisors (131364983).

649977865 is a wasteful number, since it uses less digits than its factorization.

649977865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228239.

The product of its digits is 22861440, while the sum is 61.

The square root of 649977865 is about 25494.6634612030. The cubic root of 649977865 is about 866.2292723049.

The spelling of 649977865 in words is "six hundred forty-nine million, nine hundred seventy-seven thousand, eight hundred sixty-five".