261610481388 has 72 divisors (see below), whose sum is σ = 638319600576. Its totient is φ = 83385764000.

The previous prime is 261610481383. The next prime is 261610481393. The reversal of 261610481388 is 883184016162.

It is an interprime number because it is at equal distance from previous prime (261610481383) and next prime (261610481393).

It is a super-2 number, since 2×261610481388² (a number of 24 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (261610481381) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35107063 + ... + 35114513.

It is an arithmetic number, because the mean of its divisors is an integer number (8865550008).

Almost surely, 2^261610481388 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261610481388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319159800288).

261610481388 is an abundant number, since it is smaller than the sum of its proper divisors (376709119188).

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

261610481388 is a wasteful number, since it uses less digits than its factorization.

261610481388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13035 (or 13010 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 48.

The spelling of 261610481388 in words is "two hundred sixty-one billion, six hundred ten million, four hundred eighty-one thousand, three hundred eighty-eight".