81066442 has 8 divisors (see below), whose sum is σ = 121760100. Its totient is φ = 40479744.

The previous prime is 81066409. The next prime is 81066473. The reversal of 81066442 is 24466018.

It can be written as a sum of positive squares in 2 ways, for example, as 71757841 + 9308601 = 8471^2 + 3051^2 .

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

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, 24817 + ... + 27892.

Almost surely, 2^81066442 is an apocalyptic number.

81066442 is a deficient number, since it is larger than the sum of its proper divisors (40693658).

81066442 is a wasteful number, since it uses less digits than its factorization.

81066442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53480.

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 81066442 is about 9003.6904655813. The cubic root of 81066442 is about 432.7931423969.

The spelling of 81066442 in words is "eighty-one million, sixty-six thousand, four hundred forty-two".