28878643 has 2 divisors, whose sum is σ = 28878644. Its totient is φ = 28878642.

The previous prime is 28878601. The next prime is 28878653. The reversal of 28878643 is 34687882.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28878643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28878593 and 28878602.

It is not a weakly prime, because it can be changed into another prime (28878653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14439321 + 14439322.

It is an arithmetic number, because the mean of its divisors is an integer number (14439322).

Almost surely, 2^28878643 is an apocalyptic number.

28878643 is a deficient number, since it is larger than the sum of its proper divisors (1).

28878643 is an equidigital number, since it uses as much as digits as its factorization.

28878643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 516096, while the sum is 46.

The square root of 28878643 is about 5373.8852797580. The cubic root of 28878643 is about 306.8025234272.

The spelling of 28878643 in words is "twenty-eight million, eight hundred seventy-eight thousand, six hundred forty-three".