28149481 has 2 divisors, whose sum is σ = 28149482. Its totient is φ = 28149480.

The previous prime is 28149479. The next prime is 28149491. The reversal of 28149481 is 18494182.

28149481 is nontrivially palindromic in base 8.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19053225 + 9096256 = 4365^2 + 3016^2 .

It is a cyclic number.

It is not a de Polignac number, because 28149481 - 2¹ = 28149479 is a prime.

It is a super-2 number, since 2×28149481² = 1584786561138722, which contains 22 as substring.

Together with 28149479, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28149481.

It is not a weakly prime, because it can be changed into another prime (28149421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14074740 + 14074741.

It is an arithmetic number, because the mean of its divisors is an integer number (14074741).

Almost surely, 2^28149481 is an apocalyptic number.

It is an amenable number.

28149481 is a deficient number, since it is larger than the sum of its proper divisors (1).

28149481 is an equidigital number, since it uses as much as digits as its factorization.

28149481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18432, while the sum is 37.

The square root of 28149481 is about 5305.6084476712. The cubic root of 28149481 is about 304.1983102710.

The spelling of 28149481 in words is "twenty-eight million, one hundred forty-nine thousand, four hundred eighty-one".