647657471 has 2 divisors, whose sum is σ = 647657472. Its totient is φ = 647657470.

The previous prime is 647657447. The next prime is 647657477. The reversal of 647657471 is 174756746.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 647657471 - 2⁶ = 647657407 is a prime.

It is a super-3 number, since 3×647657471³ (a number of 27 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (647657477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323828735 + 323828736.

It is an arithmetic number, because the mean of its divisors is an integer number (323828736).

Almost surely, 2^647657471 is an apocalyptic number.

647657471 is a deficient number, since it is larger than the sum of its proper divisors (1).

647657471 is an equidigital number, since it uses as much as digits as its factorization.

647657471 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 987840, while the sum is 47.

The square root of 647657471 is about 25449.1153284353. The cubic root of 647657471 is about 865.1972423781.

The spelling of 647657471 in words is "six hundred forty-seven million, six hundred fifty-seven thousand, four hundred seventy-one".