261286986 has 8 divisors (see below), whose sum is σ = 522573984. Its totient is φ = 87095660.

The previous prime is 261286943. The next prime is 261287009. The reversal of 261286986 is 689682162.

It is a happy number.

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

261286986 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21773910 + ... + 21773921.

It is an arithmetic number, because the mean of its divisors is an integer number (65321748).

Almost surely, 2^261286986 is an apocalyptic number.

261286986 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

261286986 is a wasteful number, since it uses less digits than its factorization.

261286986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43547836.

The product of its digits is 497664, while the sum is 48.

The square root of 261286986 is about 16164.3739748869. The cubic root of 261286986 is about 639.3017988032.

It can be divided in two parts, 2612 and 86986, that added together give a palindrome (89598).

The spelling of 261286986 in words is "two hundred sixty-one million, two hundred eighty-six thousand, nine hundred eighty-six".