16677777740221 has 16 divisors (see below), whose sum is σ = 18038535396336. Its totient is φ = 15328147378176.

The previous prime is 16677777740213. The next prime is 16677777740369. The reversal of 16677777740221 is 12204777777661.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 5340785708196 + 11336992032025 = 2311014^2 + 3367045^2 .

It is a cyclic number.

It is not a de Polignac number, because 16677777740221 - 2³ = 16677777740213 is a prime.

It is a super-2 number, since 2×16677777740221² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16677777741221) 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, 80204041 + ... + 80411713.

It is an arithmetic number, because the mean of its divisors is an integer number (1127408462271).

Almost surely, 2^{16677777740221} is an apocalyptic number.

It is an amenable number.

16677777740221 is a deficient number, since it is larger than the sum of its proper divisors (1360757656115).

16677777740221 is a wasteful number, since it uses less digits than its factorization.

16677777740221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234432.

The product of its (nonzero) digits is 67765824, while the sum is 64.

The spelling of 16677777740221 in words is "sixteen trillion, six hundred seventy-seven billion, seven hundred seventy-seven million, seven hundred forty thousand, two hundred twenty-one".