81811052 has 12 divisors (see below), whose sum is σ = 145596360. Its totient is φ = 40212096.

The previous prime is 81811039. The next prime is 81811073. The reversal of 81811052 is 25011818.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173093 + ... + 173564.

It is an arithmetic number, because the mean of its divisors is an integer number (12133030).

Almost surely, 2^81811052 is an apocalyptic number.

It is an amenable number.

81811052 is a deficient number, since it is larger than the sum of its proper divisors (63785308).

81811052 is a wasteful number, since it uses less digits than its factorization.

81811052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346720 (or 346718 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 81811052 is about 9044.9462132176. The cubic root of 81811052 is about 434.1142004470.

The spelling of 81811052 in words is "eighty-one million, eight hundred eleven thousand, fifty-two".