647238397 has 16 divisors (see below), whose sum is σ = 706155520. Its totient is φ = 593190000.

The previous prime is 647238379. The next prime is 647238407. The reversal of 647238397 is 793832746.

647238397 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-647238397 is a prime.

It is a super-2 number, since 2×647238397² = 837835085102259218, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 647238397.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647238307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 330772 + ... + 332722.

It is an arithmetic number, because the mean of its divisors is an integer number (44134720).

Almost surely, 2^647238397 is an apocalyptic number.

It is an amenable number.

647238397 is a deficient number, since it is larger than the sum of its proper divisors (58917123).

647238397 is a wasteful number, since it uses less digits than its factorization.

647238397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2141 (or 2115 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 49.

The square root of 647238397 is about 25440.8804289474. The cubic root of 647238397 is about 865.0105902676.

The spelling of 647238397 in words is "six hundred forty-seven million, two hundred thirty-eight thousand, three hundred ninety-seven".