81261130 has 16 divisors (see below), whose sum is σ = 146594304. Its totient is φ = 32432400.

The previous prime is 81261127. The next prime is 81261143. The reversal of 81261130 is 3116218.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4146 + ... + 13405.

It is an arithmetic number, because the mean of its divisors is an integer number (9162144).

Almost surely, 2^81261130 is an apocalyptic number.

81261130 is a deficient number, since it is larger than the sum of its proper divisors (65333174).

81261130 is a wasteful number, since it uses less digits than its factorization.

81261130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18021.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 81261130 is about 9014.4955488369. The cubic root of 81261130 is about 433.1393286726.

Adding to 81261130 its reverse (3116218), we get a palindrome (84377348).

The spelling of 81261130 in words is "eighty-one million, two hundred sixty-one thousand, one hundred thirty".