261101960 has 64 divisors (see below), whose sum is σ = 682456320. Its totient is φ = 88047360.

The previous prime is 261101941. The next prime is 261101989. The reversal of 261101960 is 69101162.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9437 + ... + 24723.

It is an arithmetic number, because the mean of its divisors is an integer number (10663380).

Almost surely, 2^261101960 is an apocalyptic number.

261101960 is a gapful number since it is divisible by the number (20) 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 261101960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (341228160).

261101960 is an abundant number, since it is smaller than the sum of its proper divisors (421354360).

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

261101960 is a wasteful number, since it uses less digits than its factorization.

261101960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15366 (or 15362 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 261101960 is about 16158.6496960606. The cubic root of 261101960 is about 639.1508595511.

The spelling of 261101960 in words is "two hundred sixty-one million, one hundred one thousand, nine hundred sixty".