261626856 has 48 divisors (see below), whose sum is σ = 676306560. Its totient is φ = 84253440.

The previous prime is 261626851. The next prime is 261626861. The reversal of 261626856 is 658626162.

It is an interprime number because it is at equal distance from previous prime (261626851) and next prime (261626861).

It is a super-2 number, since 2×261626856² = 136897223560889472, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (261626851) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 440896 + ... + 441488.

It is an arithmetic number, because the mean of its divisors is an integer number (14089720).

Almost surely, 2^261626856 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 261626856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (338153280).

261626856 is an abundant number, since it is smaller than the sum of its proper divisors (414679704).

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

261626856 is an equidigital number, since it uses as much as digits as its factorization.

261626856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1226 (or 629 counting only the distinct ones).

The product of its digits is 207360, while the sum is 42.

The square root of 261626856 is about 16174.8834926252. The cubic root of 261626856 is about 639.5788700862.

The spelling of 261626856 in words is "two hundred sixty-one million, six hundred twenty-six thousand, eight hundred fifty-six".