647674217 has 2 divisors, whose sum is σ = 647674218. Its totient is φ = 647674216.

The previous prime is 647674201. The next prime is 647674231. The reversal of 647674217 is 712476746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 628454761 + 19219456 = 25069^2 + 4384^2 .

It is a cyclic number.

It is not a de Polignac number, because 647674217 - 2⁴ = 647674201 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (647674277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323837108 + 323837109.

It is an arithmetic number, because the mean of its divisors is an integer number (323837109).

Almost surely, 2^647674217 is an apocalyptic number.

It is an amenable number.

647674217 is a deficient number, since it is larger than the sum of its proper divisors (1).

647674217 is an equidigital number, since it uses as much as digits as its factorization.

647674217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 395136, while the sum is 44.

The square root of 647674217 is about 25449.4443357807. Note that the first 3 decimals coincide. The cubic root of 647674217 is about 865.2046992354.

The spelling of 647674217 in words is "six hundred forty-seven million, six hundred seventy-four thousand, two hundred seventeen".