261870756 has 96 divisors (see below), whose sum is σ = 724711680. Its totient is φ = 72036864.

The previous prime is 261870691. The next prime is 261870757. The reversal of 261870756 is 657078162.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (261870757) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 338386 + ... + 339158.

It is an arithmetic number, because the mean of its divisors is an integer number (7549080).

Almost surely, 2^261870756 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 261870756, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (362355840).

261870756 is an abundant number, since it is smaller than the sum of its proper divisors (462840924).

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

261870756 is a wasteful number, since it uses less digits than its factorization.

261870756 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 933 (or 931 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 42.

The square root of 261870756 is about 16182.4212032687. The cubic root of 261870756 is about 639.7775561580. Note that the first 3 decimals are identical.

The spelling of 261870756 in words is "two hundred sixty-one million, eight hundred seventy thousand, seven hundred fifty-six".