646868767 has 8 divisors (see below), whose sum is σ = 691457760. Its totient is φ = 603651840.

The previous prime is 646868753. The next prime is 646868771. The reversal of 646868767 is 767868646.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 646868767 - 2⁷ = 646868639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646868797) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 342042 + ... + 343927.

It is an arithmetic number, because the mean of its divisors is an integer number (86432220).

Almost surely, 2^646868767 is an apocalyptic number.

646868767 is a deficient number, since it is larger than the sum of its proper divisors (44588993).

646868767 is a wasteful number, since it uses less digits than its factorization.

646868767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686033.

The product of its digits is 16257024, while the sum is 58.

The square root of 646868767 is about 25433.6149023296. The cubic root of 646868767 is about 864.8458932252.

The spelling of 646868767 in words is "six hundred forty-six million, eight hundred sixty-eight thousand, seven hundred sixty-seven".