28214881 has 4 divisors (see below), whose sum is σ = 28228500. Its totient is φ = 28201264.

The previous prime is 28214873. The next prime is 28214933. The reversal of 28214881 is 18841282.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14561856 + 13653025 = 3816^2 + 3695^2 .

It is a cyclic number.

It is not a de Polignac number, because 28214881 - 2³ = 28214873 is a prime.

It is a super-2 number, since 2×28214881² = 1592159019688322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28214801) 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, 2986 + ... + 8083.

It is an arithmetic number, because the mean of its divisors is an integer number (7057125).

Almost surely, 2^28214881 is an apocalyptic number.

It is an amenable number.

28214881 is a deficient number, since it is larger than the sum of its proper divisors (13619).

28214881 is a wasteful number, since it uses less digits than its factorization.

28214881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13618.

The product of its digits is 8192, while the sum is 34.

The square root of 28214881 is about 5311.7681613564. The cubic root of 28214881 is about 304.4337104933.

The spelling of 28214881 in words is "twenty-eight million, two hundred fourteen thousand, eight hundred eighty-one".