644062260446 has 32 divisors (see below), whose sum is σ = 1066513144032. Its totient is φ = 289267292160.

The previous prime is 644062260407. The next prime is 644062260449.

644062260446 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×644062260446² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 644062260397 and 644062260406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644062260449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1072100 + ... + 1561256.

It is an arithmetic number, because the mean of its divisors is an integer number (33328535751).

Almost surely, 2^644062260446 is an apocalyptic number.

644062260446 is a deficient number, since it is larger than the sum of its proper divisors (422450883586).

644062260446 is a wasteful number, since it uses less digits than its factorization.

644062260446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489884.

The product of its (nonzero) digits is 1327104, while the sum is 44.

The spelling of 644062260446 in words is "six hundred forty-four billion, sixty-two million, two hundred sixty thousand, four hundred forty-six".