2145772720 has 360 divisors, whose sum is σ = 6518957760. Its totient is φ = 654151680.

The previous prime is 2145772687. The next prime is 2145772723. The reversal of 2145772720 is 272775412.

It is a self number, because there is not a number n which added to its sum of digits gives 2145772720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2145772723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 27161641 + ... + 27161719.

It is an arithmetic number, because the mean of its divisors is an integer number (18108216).

Almost surely, 2^2145772720 is an apocalyptic number.

2145772720 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 2145772720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3259478880).

2145772720 is an abundant number, since it is smaller than the sum of its proper divisors (4373185040).

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

2145772720 is a wasteful number, since it uses less digits than its factorization.

2145772720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173 (or 147 counting only the distinct ones).

The product of its (nonzero) digits is 54880, while the sum is 37.

The square root of 2145772720 is about 46322.4861163561. The cubic root of 2145772720 is about 1289.8164352308.

The spelling of 2145772720 in words is "two billion, one hundred forty-five million, seven hundred seventy-two thousand, seven hundred twenty".