686944747 has 2 divisors, whose sum is σ = 686944748. Its totient is φ = 686944746.

The previous prime is 686944711. The next prime is 686944751. The reversal of 686944747 is 747449686.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-686944747 is a prime.

It is not a weakly prime, because it can be changed into another prime (686944757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343472373 + 343472374.

It is an arithmetic number, because the mean of its divisors is an integer number (343472374).

Almost surely, 2^686944747 is an apocalyptic number.

686944747 is a deficient number, since it is larger than the sum of its proper divisors (1).

686944747 is an equidigital number, since it uses as much as digits as its factorization.

686944747 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8128512, while the sum is 55.

The square root of 686944747 is about 26209.6308062514. The cubic root of 686944747 is about 882.3494154117.

It can be divided in two parts, 68694 and 4747, that added together give a square (73441 = 271²).

The spelling of 686944747 in words is "six hundred eighty-six million, nine hundred forty-four thousand, seven hundred forty-seven".