15222749 has 4 divisors (see below), whose sum is σ = 15233820. Its totient is φ = 15211680.

The previous prime is 15222719. The next prime is 15222761. The reversal of 15222749 is 94722251.

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 13579225 + 1643524 = 3685^2 + 1282^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15222749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15222719) 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, 3122 + ... + 6339.

It is an arithmetic number, because the mean of its divisors is an integer number (3808455).

Almost surely, 2^15222749 is an apocalyptic number.

It is an amenable number.

15222749 is a deficient number, since it is larger than the sum of its proper divisors (11071).

15222749 is an equidigital number, since it uses as much as digits as its factorization.

15222749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11070.

The product of its digits is 10080, while the sum is 32.

The square root of 15222749 is about 3901.6341448168. The cubic root of 15222749 is about 247.8359835120.

The spelling of 15222749 in words is "fifteen million, two hundred twenty-two thousand, seven hundred forty-nine".