261111098160 has 720 divisors, whose sum is σ = 1007942487552. Its totient is φ = 60471290880.

The previous prime is 261111098021. The next prime is 261111098167. The reversal of 261111098160 is 61890111162.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (261111098167) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 176068779 + ... + 176070261.

Almost surely, 2^261111098160 is an apocalyptic number.

261111098160 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 261111098160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (503971243776).

261111098160 is an abundant number, since it is smaller than the sum of its proper divisors (746831389392).

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

261111098160 is a wasteful number, since it uses less digits than its factorization.

261111098160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1614 (or 1594 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The spelling of 261111098160 in words is "two hundred sixty-one billion, one hundred eleven million, ninety-eight thousand, one hundred sixty".