28993213 has 2 divisors, whose sum is σ = 28993214. Its totient is φ = 28993212.

The previous prime is 28993207. The next prime is 28993241. The reversal of 28993213 is 31239982.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26811684 + 2181529 = 5178^2 + 1477^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28993213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28963213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14496606 + 14496607.

It is an arithmetic number, because the mean of its divisors is an integer number (14496607).

Almost surely, 2^28993213 is an apocalyptic number.

It is an amenable number.

28993213 is a deficient number, since it is larger than the sum of its proper divisors (1).

28993213 is an equidigital number, since it uses as much as digits as its factorization.

28993213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23328, while the sum is 37.

The square root of 28993213 is about 5384.5346131305. The cubic root of 28993213 is about 307.2077130960.

The spelling of 28993213 in words is "twenty-eight million, nine hundred ninety-three thousand, two hundred thirteen".