28643437 has 4 divisors (see below), whose sum is σ = 28809180. Its totient is φ = 28477696.

The previous prime is 28643429. The next prime is 28643443. The reversal of 28643437 is 73434682.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73434682 = 2 ⋅36717341.

It can be written as a sum of positive squares in 2 ways, for example, as 12595401 + 16048036 = 3549^2 + 4006^2 .

It is a cyclic number.

It is not a de Polignac number, because 28643437 - 2³ = 28643429 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28643396 and 28643405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28643737) 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, 82612 + ... + 82957.

It is an arithmetic number, because the mean of its divisors is an integer number (7202295).

Almost surely, 2^28643437 is an apocalyptic number.

It is an amenable number.

28643437 is a deficient number, since it is larger than the sum of its proper divisors (165743).

28643437 is a wasteful number, since it uses less digits than its factorization.

28643437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165742.

The product of its digits is 96768, while the sum is 37.

The square root of 28643437 is about 5351.9563712721. The cubic root of 28643437 is about 305.9673203314.

The spelling of 28643437 in words is "twenty-eight million, six hundred forty-three thousand, four hundred thirty-seven".