261636238 has 8 divisors (see below), whose sum is σ = 392657832. Its totient is φ = 130750296.

The previous prime is 261636233. The next prime is 261636253. The reversal of 261636238 is 832636162.

261636238 is nontrivially palindromic in base 6.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 261636197 and 261636206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261636233) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28945 + ... + 36892.

It is an arithmetic number, because the mean of its divisors is an integer number (49082229).

Almost surely, 2^261636238 is an apocalyptic number.

261636238 is a deficient number, since it is larger than the sum of its proper divisors (131021594).

261636238 is a wasteful number, since it uses less digits than its factorization.

261636238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67826.

The product of its digits is 62208, while the sum is 37.

The square root of 261636238 is about 16175.1735075702. The cubic root of 261636238 is about 639.5865151439.

The spelling of 261636238 in words is "two hundred sixty-one million, six hundred thirty-six thousand, two hundred thirty-eight".