28281377 has 4 divisors (see below), whose sum is σ = 28365636. Its totient is φ = 28197120.

The previous prime is 28281371. The next prime is 28281389. The reversal of 28281377 is 77318282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77318282 = 2 ⋅38659141.

It can be written as a sum of positive squares in 2 ways, for example, as 19749136 + 8532241 = 4444^2 + 2921^2 .

It is a cyclic number.

It is not a de Polignac number, because 28281377 - 2¹⁰ = 28280353 is a prime.

It is a super-2 number, since 2×28281377² = 1599672570032258, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28281377.

It is not an unprimeable number, because it can be changed into a prime (28281371) 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, 41624 + ... + 42297.

It is an arithmetic number, because the mean of its divisors is an integer number (7091409).

Almost surely, 2^28281377 is an apocalyptic number.

It is an amenable number.

28281377 is a deficient number, since it is larger than the sum of its proper divisors (84259).

28281377 is an equidigital number, since it uses as much as digits as its factorization.

28281377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84258.

The product of its digits is 37632, while the sum is 38.

The square root of 28281377 is about 5318.0237870848. The cubic root of 28281377 is about 304.6726829893.

The spelling of 28281377 in words is "twenty-eight million, two hundred eighty-one thousand, three hundred seventy-seven".