2720226521 has 4 divisors (see below), whose sum is σ = 2757489972. Its totient is φ = 2682963072.

The previous prime is 2720226469. The next prime is 2720226529. The reversal of 2720226521 is 1256220272.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2205617296 + 514609225 = 46964^2 + 22685^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2720226521 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2720226529) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18631616 + ... + 18631761.

It is an arithmetic number, because the mean of its divisors is an integer number (689372493).

Almost surely, 2^2720226521 is an apocalyptic number.

It is an amenable number.

2720226521 is a deficient number, since it is larger than the sum of its proper divisors (37263451).

2720226521 is an equidigital number, since it uses as much as digits as its factorization.

2720226521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37263450.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 2720226521 is about 52155.7908673620. The cubic root of 2720226521 is about 1395.9451585654.

Adding to 2720226521 its reverse (1256220272), we get a palindrome (3976446793).

The spelling of 2720226521 in words is "two billion, seven hundred twenty million, two hundred twenty-six thousand, five hundred twenty-one".