261685248 has 136 divisors (see below), whose sum is σ = 767551776. Its totient is φ = 79298560.

The previous prime is 261685231. The next prime is 261685261. The reversal of 261685248 is 842586162.

Its product of digits (184320) is a multiple of the sum of its prime divisors (16).

It is a nialpdrome in base 16.

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, 23789563 + ... + 23789573.

Almost surely, 2^261685248 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 261685248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (383775888).

261685248 is an abundant number, since it is smaller than the sum of its proper divisors (505866528).

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

261685248 is an frugal number, since it uses more digits than its factorization.

261685248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68 (or 16 counting only the distinct ones).

The product of its digits is 184320, while the sum is 42.

The square root of 261685248 is about 16176.6884126511. The cubic root of 261685248 is about 639.6264486769.

The spelling of 261685248 in words is "two hundred sixty-one million, six hundred eighty-five thousand, two hundred forty-eight".