2173639680 has 264 divisors, whose sum is σ = 7713783792. Its totient is φ = 565641216.

The previous prime is 2173639651. The next prime is 2173639681. The reversal of 2173639680 is 869363712.

2173639680 is a `hidden beast` number, since 2 + 1 + 7 + 3 + 639 + 6 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2173639681) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1980892 + ... + 1981988.

It is an arithmetic number, because the mean of its divisors is an integer number (29218878).

Almost surely, 2^2173639680 is an apocalyptic number.

2173639680 is a gapful number since it is divisible by the number (20) 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 2173639680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3856891896).

2173639680 is an abundant number, since it is smaller than the sum of its proper divisors (5540144112).

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

2173639680 is a wasteful number, since it uses less digits than its factorization.

2173639680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1171 (or 1150 counting only the distinct ones).

The product of its (nonzero) digits is 326592, while the sum is 45.

The square root of 2173639680 is about 46622.3088231374. The cubic root of 2173639680 is about 1295.3760142036.

It can be divided in two parts, 21736 and 39680, that added together give a palindrome (61416).

The spelling of 2173639680 in words is "two billion, one hundred seventy-three million, six hundred thirty-nine thousand, six hundred eighty".