81066738 has 16 divisors (see below), whose sum is σ = 162376416. Its totient is φ = 26981760.

The previous prime is 81066721. The next prime is 81066757. The reversal of 81066738 is 83766018.

It is a junction number, because it is equal to n+sod(n) for n = 81066696 and 81066705.

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, 5631 + ... + 13922.

It is an arithmetic number, because the mean of its divisors is an integer number (10148526).

Almost surely, 2^81066738 is an apocalyptic number.

81066738 is an abundant number, since it is smaller than the sum of its proper divisors (81309678).

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

81066738 is a wasteful number, since it uses less digits than its factorization.

81066738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20249.

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 81066738 is about 9003.7069032705. The cubic root of 81066738 is about 432.7936691525.

The spelling of 81066738 in words is "eighty-one million, sixty-six thousand, seven hundred thirty-eight".