647394321 has 32 divisors (see below), whose sum is σ = 1009657600. Its totient is φ = 368831232.

The previous prime is 647394313. The next prime is 647394329. The reversal of 647394321 is 123493746.

It is an interprime number because it is at equal distance from previous prime (647394313) and next prime (647394329).

It is not a de Polignac number, because 647394321 - 2³ = 647394313 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 647394321.

It is not an unprimeable number, because it can be changed into a prime (647394329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 444831 + ... + 446283.

It is an arithmetic number, because the mean of its divisors is an integer number (31551800).

Almost surely, 2^647394321 is an apocalyptic number.

It is an amenable number.

647394321 is a deficient number, since it is larger than the sum of its proper divisors (362263279).

647394321 is a wasteful number, since it uses less digits than its factorization.

647394321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1910 (or 1896 counting only the distinct ones).

The product of its digits is 108864, while the sum is 39.

The square root of 647394321 is about 25443.9446823797. The cubic root of 647394321 is about 865.0800469431.

The spelling of 647394321 in words is "six hundred forty-seven million, three hundred ninety-four thousand, three hundred twenty-one".