20411261 has 4 divisors (see below), whose sum is σ = 21981372. Its totient is φ = 18841152.

The previous prime is 20411249. The next prime is 20411267. The reversal of 20411261 is 16211402.

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 8231161 + 12180100 = 2869^2 + 3490^2 .

It is a cyclic number.

It is not a de Polignac number, because 20411261 - 2¹⁸ = 20149117 is a prime.

It is a super-2 number, since 2×20411261² = 833239151220242, 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 (20411267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 785036 + ... + 785061.

It is an arithmetic number, because the mean of its divisors is an integer number (5495343).

Almost surely, 2^20411261 is an apocalyptic number.

It is an amenable number.

20411261 is a deficient number, since it is larger than the sum of its proper divisors (1570111).

20411261 is a wasteful number, since it uses less digits than its factorization.

20411261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1570110.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 20411261 is about 4517.8823579195. The cubic root of 20411261 is about 273.2897093114.

Adding to 20411261 its reverse (16211402), we get a palindrome (36622663).

The spelling of 20411261 in words is "twenty million, four hundred eleven thousand, two hundred sixty-one".