16679234221 has 4 divisors (see below), whose sum is σ = 17962252252. Its totient is φ = 15396216192.

The previous prime is 16679234219. The next prime is 16679234263. The reversal of 16679234221 is 12243297661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12243297661 = 7 ⋅1749042523.

It can be written as a sum of positive squares in 2 ways, for example, as 11022690121 + 5656544100 = 104989^2 + 75210^2 .

It is a cyclic number.

It is not a de Polignac number, because 16679234221 - 2¹ = 16679234219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16679234321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 641508996 + ... + 641509021.

It is an arithmetic number, because the mean of its divisors is an integer number (4490563063).

Almost surely, 2^16679234221 is an apocalyptic number.

It is an amenable number.

16679234221 is a deficient number, since it is larger than the sum of its proper divisors (1283018031).

16679234221 is a wasteful number, since it uses less digits than its factorization.

16679234221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1283018030.

The product of its digits is 217728, while the sum is 43.

The spelling of 16679234221 in words is "sixteen billion, six hundred seventy-nine million, two hundred thirty-four thousand, two hundred twenty-one".