646770862377663 has 4 divisors (see below), whose sum is σ = 862361149836888. Its totient is φ = 431180574918440.

The previous prime is 646770862377649. The next prime is 646770862377713. The reversal of 646770862377663 is 366773268077646.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 646770862377663 - 2⁸ = 646770862377407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646770862377623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107795143729608 + ... + 107795143729613.

It is an arithmetic number, because the mean of its divisors is an integer number (215590287459222).

Almost surely, 2^{646770862377663} is an apocalyptic number.

646770862377663 is a deficient number, since it is larger than the sum of its proper divisors (215590287459225).

646770862377663 is a wasteful number, since it uses less digits than its factorization.

646770862377663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215590287459224.

The product of its (nonzero) digits is 10754021376, while the sum is 78.

The spelling of 646770862377663 in words is "six hundred forty-six trillion, seven hundred seventy billion, eight hundred sixty-two million, three hundred seventy-seven thousand, six hundred sixty-three".