856642825291 has 48 divisors (see below), whose sum is σ = 1001968289280. Its totient is φ = 729752760000.

The previous prime is 856642825289. The next prime is 856642825307. The reversal of 856642825291 is 192528246658.

It is not a de Polignac number, because 856642825291 - 2¹ = 856642825289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (856642825201) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 184738425 + ... + 184743061.

It is an arithmetic number, because the mean of its divisors is an integer number (20874339360).

Almost surely, 2^856642825291 is an apocalyptic number.

856642825291 is a deficient number, since it is larger than the sum of its proper divisors (145325463989).

856642825291 is a wasteful number, since it uses less digits than its factorization.

856642825291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5536 (or 5525 counting only the distinct ones).

The product of its digits is 16588800, while the sum is 58.

The spelling of 856642825291 in words is "eight hundred fifty-six billion, six hundred forty-two million, eight hundred twenty-five thousand, two hundred ninety-one".