646217712646 has 16 divisors (see below), whose sum is σ = 1091558366208. Its totient is φ = 284259990600.

The previous prime is 646217712641. The next prime is 646217712649.

646217712646 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 646217712593 and 646217712602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646217712641) 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, 473765970 + ... + 473767333.

It is an arithmetic number, because the mean of its divisors is an integer number (68222397888).

Almost surely, 2^646217712646 is an apocalyptic number.

646217712646 is a deficient number, since it is larger than the sum of its proper divisors (445340653562).

646217712646 is a wasteful number, since it uses less digits than its factorization.

646217712646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 947533347.

The product of its digits is 4064256, while the sum is 52.

The spelling of 646217712646 in words is "six hundred forty-six billion, two hundred seventeen million, seven hundred twelve thousand, six hundred forty-six".