261641238 has 32 divisors (see below), whose sum is σ = 549351936. Its totient is φ = 82915008.

The previous prime is 261641179. The next prime is 261641249. The reversal of 261641238 is 832146162.

It is a super-2 number, since 2×261641238² = 136912274844345288, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 261641199 and 261641208.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 17370 + ... + 28722.

It is an arithmetic number, because the mean of its divisors is an integer number (17167248).

Almost surely, 2^261641238 is an apocalyptic number.

261641238 is an abundant number, since it is smaller than the sum of its proper divisors (287710698).

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

261641238 is a wasteful number, since it uses less digits than its factorization.

261641238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11548.

The product of its digits is 13824, while the sum is 33.

The square root of 261641238 is about 16175.3280646792. The cubic root of 261641238 is about 639.5905893912.

The spelling of 261641238 in words is "two hundred sixty-one million, six hundred forty-one thousand, two hundred thirty-eight".