28646397 has 12 divisors (see below), whose sum is σ = 44561244. Its totient is φ = 17628480.

The previous prime is 28646389. The next prime is 28646407. The reversal of 28646397 is 79364682.

28646397 is a `hidden beast` number, since 2 + 8 + 6 + 4 + 639 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 4968441 + 23677956 = 2229^2 + 4866^2 .

It is not a de Polignac number, because 28646397 - 2³ = 28646389 is a prime.

It is a super-2 number, since 2×28646397² = 1641232122163218, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28646347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 122304 + ... + 122537.

It is an arithmetic number, because the mean of its divisors is an integer number (3713437).

Almost surely, 2^28646397 is an apocalyptic number.

It is an amenable number.

28646397 is a deficient number, since it is larger than the sum of its proper divisors (15914847).

28646397 is a wasteful number, since it uses less digits than its factorization.

28646397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244860 (or 244857 counting only the distinct ones).

The product of its digits is 435456, while the sum is 45.

The square root of 28646397 is about 5352.2328985200. The cubic root of 28646397 is about 305.9778594771.

It can be divided in two parts, 2864 and 6397, that added together give a cube (9261 = 21³).

The spelling of 28646397 in words is "twenty-eight million, six hundred forty-six thousand, three hundred ninety-seven".