261341161320 has 256 divisors, whose sum is σ = 802444942080. Its totient is φ = 68078796800.

The previous prime is 261341161303. The next prime is 261341161321. The reversal of 261341161320 is 23161143162.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (261341161321) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 407708200 + ... + 407708840.

It is an arithmetic number, because the mean of its divisors is an integer number (3134550555).

Almost surely, 2^261341161320 is an apocalyptic number.

261341161320 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 261341161320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401222471040).

261341161320 is an abundant number, since it is smaller than the sum of its proper divisors (541103780760).

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

261341161320 is a wasteful number, since it uses less digits than its factorization.

261341161320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1156 (or 1152 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The spelling of 261341161320 in words is "two hundred sixty-one billion, three hundred forty-one million, one hundred sixty-one thousand, three hundred twenty".