261839439 has 16 divisors (see below), whose sum is σ = 388399200. Its totient is φ = 174339648.

The previous prime is 261839359. The next prime is 261839441. The reversal of 261839439 is 934938162.

It is a happy number.

It is not a de Polignac number, because 261839439 - 2⁷ = 261839311 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 261839394 and 261839403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261839449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17347 + ... + 28715.

It is an arithmetic number, because the mean of its divisors is an integer number (24274950).

Almost surely, 2^261839439 is an apocalyptic number.

261839439 is a deficient number, since it is larger than the sum of its proper divisors (126559761).

261839439 is a wasteful number, since it uses less digits than its factorization.

261839439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12231 (or 12225 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 261839439 is about 16181.4535502840. The cubic root of 261839439 is about 639.7520515761.

The spelling of 261839439 in words is "two hundred sixty-one million, eight hundred thirty-nine thousand, four hundred thirty-nine".