81330001 has 8 divisors (see below), whose sum is σ = 84959424. Its totient is φ = 77708400.

The previous prime is 81329993. The next prime is 81330017. The reversal of 81330001 is 10003318.

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

It is a cyclic number.

It is not a de Polignac number, because 81330001 - 2³ = 81329993 is a prime.

It is a super-2 number, since 2×81330001² = 13229138125320002, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81330401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32155 + ... + 34591.

It is an arithmetic number, because the mean of its divisors is an integer number (10619928).

Almost surely, 2^81330001 is an apocalyptic number.

It is an amenable number.

81330001 is a deficient number, since it is larger than the sum of its proper divisors (3629423).

81330001 is a wasteful number, since it uses less digits than its factorization.

81330001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3911.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 81330001 is about 9018.3147538772. The cubic root of 81330001 is about 433.2616598750.

Adding to 81330001 its reverse (10003318), we get a palindrome (91333319).

The spelling of 81330001 in words is "eighty-one million, three hundred thirty thousand, one".