22720513 has 4 divisors (see below), whose sum is σ = 22731220. Its totient is φ = 22709808.

The previous prime is 22720507. The next prime is 22720531. The reversal of 22720513 is 31502722.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 19820304 + 2900209 = 4452^2 + 1703^2 .

It is a cyclic number.

It is not a de Polignac number, because 22720513 - 2⁹ = 22720001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22720583) 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, 978 + ... + 6811.

It is an arithmetic number, because the mean of its divisors is an integer number (5682805).

Almost surely, 2^22720513 is an apocalyptic number.

It is an amenable number.

22720513 is a deficient number, since it is larger than the sum of its proper divisors (10707).

22720513 is an equidigital number, since it uses as much as digits as its factorization.

22720513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10706.

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 22720513 is about 4766.6039273260. The cubic root of 22720513 is about 283.2300817166.

It can be divided in two parts, 227205 and 13, that multiplied together give a triangular number (2953665 = T₂₄₃₀).

The spelling of 22720513 in words is "twenty-two million, seven hundred twenty thousand, five hundred thirteen".