646621126646 has 16 divisors (see below), whose sum is σ = 1058523475968. Its totient is φ = 293803089000.

The previous prime is 646621126643. The next prime is 646621126649.

646621126646 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (646621126643) and next prime (646621126649).

It is a junction number, because it is equal to n+sod(n) for n = 646621126594 and 646621126603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646621126643) 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, 5723030 + ... + 5834921.

It is an arithmetic number, because the mean of its divisors is an integer number (66157717248).

Almost surely, 2^646621126646 is an apocalyptic number.

646621126646 is a deficient number, since it is larger than the sum of its proper divisors (411902349322).

646621126646 is a wasteful number, since it uses less digits than its factorization.

646621126646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11560507.

The product of its digits is 2985984, while the sum is 50.

It can be divided in two parts, 6466 and 21126646, that added together give a palindrome (21133112).

The spelling of 646621126646 in words is "six hundred forty-six billion, six hundred twenty-one million, one hundred twenty-six thousand, six hundred forty-six".