81576001 has 4 divisors (see below), whose sum is σ = 87851092. Its totient is φ = 75300912.

The previous prime is 81575981. The next prime is 81576007. The reversal of 81576001 is 10067518.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10067518 = 2 ⋅5033759.

It can be written as a sum of positive squares in 2 ways, for example, as 45576001 + 36000000 = 6751^2 + 6000^2 .

It is a cyclic number.

It is not a de Polignac number, because 81576001 - 2¹¹ = 81573953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81576007) 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, 3137526 + ... + 3137551.

It is an arithmetic number, because the mean of its divisors is an integer number (21962773).

Almost surely, 2^81576001 is an apocalyptic number.

It is an amenable number.

81576001 is a deficient number, since it is larger than the sum of its proper divisors (6275091).

81576001 is a wasteful number, since it uses less digits than its factorization.

81576001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6275090.

The product of its (nonzero) digits is 1680, while the sum is 28.

The square root of 81576001 is about 9031.9433678473. The cubic root of 81576001 is about 433.6980510666.

The spelling of 81576001 in words is "eighty-one million, five hundred seventy-six thousand, one".