261251550222 has 64 divisors (see below), whose sum is σ = 581443301376. Its totient is φ = 77712180480.

The previous prime is 261251550181. The next prime is 261251550283. The reversal of 261251550222 is 222055152162.

It is a happy number.

It is a congruent number.

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, 2321938 + ... + 2431850.

It is an arithmetic number, because the mean of its divisors is an integer number (9085051584).

Almost surely, 2^261251550222 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261251550222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (290721650688).

261251550222 is an abundant number, since it is smaller than the sum of its proper divisors (320191751154).

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

261251550222 is a wasteful number, since it uses less digits than its factorization.

261251550222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110945.

The product of its (nonzero) digits is 24000, while the sum is 33.

The spelling of 261251550222 in words is "two hundred sixty-one billion, two hundred fifty-one million, five hundred fifty thousand, two hundred twenty-two".