81025001 has 4 divisors (see below), whose sum is σ = 81782352. Its totient is φ = 80267652.

The previous prime is 81024997. The next prime is 81025027. The reversal of 81025001 is 10052018.

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 81025001 - 2² = 81024997 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81025501) 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, 378515 + ... + 378728.

It is an arithmetic number, because the mean of its divisors is an integer number (20445588).

Almost surely, 2^81025001 is an apocalyptic number.

It is an amenable number.

81025001 is a deficient number, since it is larger than the sum of its proper divisors (757351).

81025001 is a wasteful number, since it uses less digits than its factorization.

81025001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 757350.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 81025001 is about 9001.3888372851. The cubic root of 81025001 is about 432.7193821692.

Adding to 81025001 its reverse (10052018), we get a palindrome (91077019).

The spelling of 81025001 in words is "eighty-one million, twenty-five thousand, one".