16643234661 has 32 divisors (see below), whose sum is σ = 24062463360. Its totient is φ = 10196637696.

The previous prime is 16643234653. The next prime is 16643234687.

16643234661 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 16643234661 - 2³ = 16643234653 is a prime.

It is a super-2 number, since 2×16643234661² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16643234611) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 699025 + ... + 722441.

It is an arithmetic number, because the mean of its divisors is an integer number (751951980).

Almost surely, 2^16643234661 is an apocalyptic number.

It is an amenable number.

16643234661 is a deficient number, since it is larger than the sum of its proper divisors (7419228699).

16643234661 is a wasteful number, since it uses less digits than its factorization.

16643234661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23813.

The product of its digits is 373248, while the sum is 42.

The spelling of 16643234661 in words is "sixteen billion, six hundred forty-three million, two hundred thirty-four thousand, six hundred sixty-one".