20612261 has 4 divisors (see below), whose sum is σ = 20628300. Its totient is φ = 20596224.

The previous prime is 20612239. The next prime is 20612269. The reversal of 20612261 is 16221602.

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 1515361 + 19096900 = 1231^2 + 4370^2 .

It is a cyclic number.

It is not a de Polignac number, because 20612261 - 2⁶ = 20612197 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 (20612269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5906 + ... + 8723.

It is an arithmetic number, because the mean of its divisors is an integer number (5157075).

Almost surely, 2^20612261 is an apocalyptic number.

It is an amenable number.

20612261 is a deficient number, since it is larger than the sum of its proper divisors (16039).

20612261 is a wasteful number, since it uses less digits than its factorization.

20612261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16038.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 20612261 is about 4540.0727967732. The cubic root of 20612261 is about 274.1838546189.

Adding to 20612261 its reverse (16221602), we get a palindrome (36833863).

The spelling of 20612261 in words is "twenty million, six hundred twelve thousand, two hundred sixty-one".