261009711072 has 480 divisors, whose sum is σ = 901792362240. Its totient is φ = 73171537920.

The previous prime is 261009711071. The next prime is 261009711113. The reversal of 261009711072 is 270117900162.

It is a happy number.

261009711072 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261009711071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 28592973 + ... + 28602099.

It is an arithmetic number, because the mean of its divisors is an integer number (1878734088).

Almost surely, 2^261009711072 is an apocalyptic number.

261009711072 is a gapful number since it is divisible by the number (22) 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 261009711072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (450896181120).

261009711072 is an abundant number, since it is smaller than the sum of its proper divisors (640782651168).

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

261009711072 is a wasteful number, since it uses less digits than its factorization.

261009711072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9236 (or 9219 counting only the distinct ones).

The product of its (nonzero) digits is 10584, while the sum is 36.

The spelling of 261009711072 in words is "two hundred sixty-one billion, nine million, seven hundred eleven thousand, seventy-two".