28342881 has 24 divisors (see below), whose sum is σ = 46941440. Its totient is φ = 16142976.

The previous prime is 28342871. The next prime is 28342901. The reversal of 28342881 is 18824382.

It is a happy number.

It is not a de Polignac number, because 28342881 - 2¹⁸ = 28080737 is a prime.

It is a super-2 number, since 2×28342881² = 1606637806760322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (28342801) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26760 + ... + 27798.

Almost surely, 2^28342881 is an apocalyptic number.

28342881 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

28342881 is a deficient number, since it is larger than the sum of its proper divisors (18598559).

28342881 is a wasteful number, since it uses less digits than its factorization.

28342881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1485 (or 1482 counting only the distinct ones).

The product of its digits is 24576, while the sum is 36.

The square root of 28342881 is about 5323.8032458009. The cubic root of 28342881 is about 304.8933820660.

The spelling of 28342881 in words is "twenty-eight million, three hundred forty-two thousand, eight hundred eighty-one".