261838870 has 16 divisors (see below), whose sum is σ = 474910128. Its totient is φ = 103935520.

The previous prime is 261838861. The next prime is 261838897. The reversal of 261838870 is 78838162.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98629 + ... + 101248.

It is an arithmetic number, because the mean of its divisors is an integer number (29681883).

Almost surely, 2^261838870 is an apocalyptic number.

261838870 is a deficient number, since it is larger than the sum of its proper divisors (213071258).

261838870 is a wasteful number, since it uses less digits than its factorization.

261838870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200015.

The product of its (nonzero) digits is 129024, while the sum is 43.

The square root of 261838870 is about 16181.4359684176. The cubic root of 261838870 is about 639.7515881633.

It can be divided in two parts, 26183 and 8870, that added together give a palindrome (35053).

The spelling of 261838870 in words is "two hundred sixty-one million, eight hundred thirty-eight thousand, eight hundred seventy".