2155067720 has 96 divisors (see below), whose sum is σ = 5432135400. Its totient is φ = 768208896.

The previous prime is 2155067687. The next prime is 2155067729. The reversal of 2155067720 is 277605512.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 120516484 + 2034551236 = 10978^2 + 45106^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2155067729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 190544 + ... + 201536.

Almost surely, 2^2155067720 is an apocalyptic number.

2155067720 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 2155067720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2716067700).

2155067720 is an abundant number, since it is smaller than the sum of its proper divisors (3277067680).

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

2155067720 is a wasteful number, since it uses less digits than its factorization.

2155067720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11059 (or 11042 counting only the distinct ones).

The product of its (nonzero) digits is 29400, while the sum is 35.

The square root of 2155067720 is about 46422.7069439084. The cubic root of 2155067720 is about 1291.6761497928.

The spelling of 2155067720 in words is "two billion, one hundred fifty-five million, sixty-seven thousand, seven hundred twenty".