2177721222768 has 320 divisors, whose sum is σ = 7752120499200. Its totient is φ = 569958405120.

The previous prime is 2177721222709. The next prime is 2177721222769. The reversal of 2177721222768 is 8672221277712.

It is a super-3 number, since 3×2177721222768³ (a number of 38 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2177721222769) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4938438 + ... + 5361306.

It is an arithmetic number, because the mean of its divisors is an integer number (24225376560).

Almost surely, 2^{2177721222768} is an apocalyptic number.

2177721222768 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2177721222768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3876060249600).

2177721222768 is an abundant number, since it is smaller than the sum of its proper divisors (5574399276432).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2177721222768 is a wasteful number, since it uses less digits than its factorization.

2177721222768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423037 (or 423025 counting only the distinct ones).

The product of its digits is 3687936, while the sum is 54.

The spelling of 2177721222768 in words is "two trillion, one hundred seventy-seven billion, seven hundred twenty-one million, two hundred twenty-two thousand, seven hundred sixty-eight".