647936973 has 6 divisors (see below), whose sum is σ = 935908974. Its totient is φ = 431957976.

The previous prime is 647936969. The next prime is 647936987. The reversal of 647936973 is 379639746.

It can be written as a sum of positive squares in only one way, i.e., 606489129 + 41447844 = 24627^2 + 6438^2 .

It is not a de Polignac number, because 647936973 - 2² = 647936969 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647936903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35996490 + ... + 35996507.

It is an arithmetic number, because the mean of its divisors is an integer number (155984829).

Almost surely, 2^647936973 is an apocalyptic number.

It is an amenable number.

647936973 is a deficient number, since it is larger than the sum of its proper divisors (287972001).

647936973 is a wasteful number, since it uses less digits than its factorization.

647936973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71993003 (or 71993000 counting only the distinct ones).

The product of its digits is 5143824, while the sum is 54.

The square root of 647936973 is about 25454.6061254147. The cubic root of 647936973 is about 865.3216855144.

The spelling of 647936973 in words is "six hundred forty-seven million, nine hundred thirty-six thousand, nine hundred seventy-three".