20732261 has 6 divisors (see below), whose sum is σ = 22788486. Its totient is φ = 18847400.

The previous prime is 20732233. The next prime is 20732263. The reversal of 20732261 is 16223702.

It can be written as a sum of positive squares in only one way, i.e., 14822500 + 5909761 = 3850^2 + 2431^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20732261 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20732263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 85550 + ... + 85791.

It is an arithmetic number, because the mean of its divisors is an integer number (3798081).

Almost surely, 2^20732261 is an apocalyptic number.

It is an amenable number.

20732261 is a deficient number, since it is larger than the sum of its proper divisors (2056225).

20732261 is a wasteful number, since it uses less digits than its factorization.

20732261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171363 (or 171352 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 20732261 is about 4553.2692650446. The cubic root of 20732261 is about 274.7149045406.

Adding to 20732261 its reverse (16223702), we get a palindrome (36955963).

It can be divided in two parts, 2073 and 2261, that added together give a palindrome (4334).

The spelling of 20732261 in words is "twenty million, seven hundred thirty-two thousand, two hundred sixty-one".