81805234 has 8 divisors (see below), whose sum is σ = 140237568. Its totient is φ = 35059380.

The previous prime is 81805219. The next prime is 81805237. The reversal of 81805234 is 43250818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 81805196 and 81805205.

It is not an unprimeable number, because it can be changed into a prime (81805237) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2921602 + ... + 2921629.

It is an arithmetic number, because the mean of its divisors is an integer number (17529696).

Almost surely, 2^81805234 is an apocalyptic number.

81805234 is a deficient number, since it is larger than the sum of its proper divisors (58432334).

81805234 is a wasteful number, since it uses less digits than its factorization.

81805234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5843240.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 81805234 is about 9044.6245914355. The cubic root of 81805234 is about 434.1039095134.

The spelling of 81805234 in words is "eighty-one million, eight hundred five thousand, two hundred thirty-four".