261897504 has 192 divisors, whose sum is σ = 804722688. Its totient is φ = 73779200.

The previous prime is 261897473. The next prime is 261897533. The reversal of 261897504 is 405798162.

261897504 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 995677 + ... + 995939.

It is an arithmetic number, because the mean of its divisors is an integer number (4191264).

Almost surely, 2^261897504 is an apocalyptic number.

261897504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261897504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (402361344).

261897504 is an abundant number, since it is smaller than the sum of its proper divisors (542825184).

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

261897504 is a wasteful number, since it uses less digits than its factorization.

261897504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351 (or 343 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 42.

The square root of 261897504 is about 16183.2476345139. The cubic root of 261897504 is about 639.7993381339.

The spelling of 261897504 in words is "two hundred sixty-one million, eight hundred ninety-seven thousand, five hundred four".