81261150 has 96 divisors (see below), whose sum is σ = 209236608. Its totient is φ = 20860800.

The previous prime is 81261143. The next prime is 81261163. The reversal of 81261150 is 5116218.

It is a self number, because there is not a number n which added to its sum of digits gives 81261150.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 759397 + ... + 759503.

It is an arithmetic number, because the mean of its divisors is an integer number (2179548).

Almost surely, 2^81261150 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81261150, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104618304).

81261150 is an abundant number, since it is smaller than the sum of its proper divisors (127975458).

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

81261150 is a wasteful number, since it uses less digits than its factorization.

81261150 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266 (or 261 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 24.

The square root of 81261150 is about 9014.4966581612. The cubic root of 81261150 is about 433.1393642074.

Adding to 81261150 its reverse (5116218), we get a palindrome (86377368).

The spelling of 81261150 in words is "eighty-one million, two hundred sixty-one thousand, one hundred fifty".