42724261 has 4 divisors (see below), whose sum is σ = 42794572. Its totient is φ = 42653952.

The previous prime is 42724237. The next prime is 42724273. The reversal of 42724261 is 16242724.

It is a happy number.

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 22420225 + 20304036 = 4735^2 + 4506^2 .

It is a cyclic number.

It is not a de Polignac number, because 42724261 - 2²¹ = 40627109 is a prime.

It is a super-2 number, since 2×42724261² = 3650724955992242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42794261) 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, 34236 + ... + 35461.

It is an arithmetic number, because the mean of its divisors is an integer number (10698643).

Almost surely, 2^42724261 is an apocalyptic number.

It is an amenable number.

42724261 is a deficient number, since it is larger than the sum of its proper divisors (70311).

42724261 is an equidigital number, since it uses as much as digits as its factorization.

42724261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70310.

The product of its digits is 5376, while the sum is 28.

The square root of 42724261 is about 6536.3798084261. The cubic root of 42724261 is about 349.5893442154.

Adding to 42724261 its reverse (16242724), we get a palindrome (58966985).

The spelling of 42724261 in words is "forty-two million, seven hundred twenty-four thousand, two hundred sixty-one".