261351936 has 120 divisors (see below), whose sum is σ = 772405920. Its totient is φ = 85026816.

The previous prime is 261351929. The next prime is 261351947. The reversal of 261351936 is 639153162.

261351936 is a `hidden beast` number, since 2 + 613 + 5 + 1 + 9 + 36 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 261351936.

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 11 ways as a sum of consecutive naturals, for example, 197485 + ... + 198803.

It is an arithmetic number, because the mean of its divisors is an integer number (6436716).

Almost surely, 2^261351936 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261351936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386202960).

261351936 is an abundant number, since it is smaller than the sum of its proper divisors (511053984).

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

261351936 is a wasteful number, since it uses less digits than its factorization.

261351936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1386 (or 1367 counting only the distinct ones).

The product of its digits is 29160, while the sum is 36.

The square root of 261351936 is about 16166.3828978532. The cubic root of 261351936 is about 639.3547663752.

The spelling of 261351936 in words is "two hundred sixty-one million, three hundred fifty-one thousand, nine hundred thirty-six".