261732220 has 36 divisors (see below), whose sum is σ = 580104504. Its totient is φ = 99180000.

The previous prime is 261732209. The next prime is 261732223. The reversal of 261732220 is 22237162.

It is a super-2 number, since 2×261732220² = 137007509972256800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261732223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10906 + ... + 25345.

It is an arithmetic number, because the mean of its divisors is an integer number (16114014).

Almost surely, 2^261732220 is an apocalyptic number.

261732220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261732220 is an abundant number, since it is smaller than the sum of its proper divisors (318372284).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261732220 is a wasteful number, since it uses less digits than its factorization.

261732220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36298 (or 36277 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 261732220 is about 16178.1401897746. The cubic root of 261732220 is about 639.6647169608.

Adding to 261732220 its reverse (22237162), we get a palindrome (283969382).

The spelling of 261732220 in words is "two hundred sixty-one million, seven hundred thirty-two thousand, two hundred twenty".