81322001 has 4 divisors (see below), whose sum is σ = 82700400. Its totient is φ = 79943604.

The previous prime is 81321991. The next prime is 81322019. The reversal of 81322001 is 10022318.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81322001 - 2²² = 77127697 is a prime.

It is a super-2 number, since 2×81322001² = 13226535693288002, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81322201) 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, 689111 + ... + 689228.

It is an arithmetic number, because the mean of its divisors is an integer number (20675100).

Almost surely, 2^81322001 is an apocalyptic number.

It is an amenable number.

81322001 is a deficient number, since it is larger than the sum of its proper divisors (1378399).

81322001 is a wasteful number, since it uses less digits than its factorization.

81322001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1378398.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 81322001 is about 9017.8712011206. The cubic root of 81322001 is about 433.2474535268.

Adding to 81322001 its reverse (10022318), we get a palindrome (91344319).

The spelling of 81322001 in words is "eighty-one million, three hundred twenty-two thousand, one".