647883909 has 6 divisors (see below), whose sum is σ = 935832326. Its totient is φ = 431922600.

The previous prime is 647883883. The next prime is 647884001. The reversal of 647883909 is 909388746.

647883909 is a `hidden beast` number, since 6 + 478 + 83 + 90 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 631114884 + 16769025 = 25122^2 + 4095^2 .

It is not a de Polignac number, because 647883909 - 2¹⁶ = 647818373 is a prime.

It is a super-2 number, since 2×647883909² = 839507119082240562, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647881909) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35993542 + ... + 35993559.

Almost surely, 2^647883909 is an apocalyptic number.

It is an amenable number.

647883909 is a deficient number, since it is larger than the sum of its proper divisors (287948417).

647883909 is a wasteful number, since it uses less digits than its factorization.

647883909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71987107 (or 71987104 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The square root of 647883909 is about 25453.5637779860. The cubic root of 647883909 is about 865.2980624948.

The spelling of 647883909 in words is "six hundred forty-seven million, eight hundred eighty-three thousand, nine hundred nine".