28622081 has 4 divisors (see below), whose sum is σ = 28917252. Its totient is φ = 28326912.

The previous prime is 28622071. The next prime is 28622089. The reversal of 28622081 is 18022682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18022682 = 2 ⋅9011341.

It can be written as a sum of positive squares in 2 ways, for example, as 6682225 + 21939856 = 2585^2 + 4684^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28622081 is a prime.

It is a super-2 number, since 2×28622081² = 1638447041541122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28622089) 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, 147440 + ... + 147633.

It is an arithmetic number, because the mean of its divisors is an integer number (7229313).

Almost surely, 2^28622081 is an apocalyptic number.

It is an amenable number.

28622081 is a deficient number, since it is larger than the sum of its proper divisors (295171).

28622081 is an equidigital number, since it uses as much as digits as its factorization.

28622081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295170.

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 28622081 is about 5349.9608409782. The cubic root of 28622081 is about 305.8912602936.

The spelling of 28622081 in words is "twenty-eight million, six hundred twenty-two thousand, eighty-one".