81041930 has 16 divisors (see below), whose sum is σ = 145982304. Its totient is φ = 32393040.

The previous prime is 81041911. The next prime is 81041963. The reversal of 81041930 is 3914018.

It is a self number, because there is not a number n which added to its sum of digits gives 81041930.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19409 + ... + 23211.

It is an arithmetic number, because the mean of its divisors is an integer number (9123894).

Almost surely, 2^81041930 is an apocalyptic number.

81041930 is a deficient number, since it is larger than the sum of its proper divisors (64940374).

81041930 is a wasteful number, since it uses less digits than its factorization.

81041930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5941.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 81041930 is about 9002.3291430607. The cubic root of 81041930 is about 432.7495168857.

Adding to 81041930 its reverse (3914018), we get a palindrome (84955948).

The spelling of 81041930 in words is "eighty-one million, forty-one thousand, nine hundred thirty".