28249657 has 2 divisors, whose sum is σ = 28249658. Its totient is φ = 28249656.

The previous prime is 28249643. The next prime is 28249691. The reversal of 28249657 is 75694282.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27678121 + 571536 = 5261^2 + 756^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28249657 is a prime.

It is a super-3 number, since 3×28249657³ (a number of 23 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (28249607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14124828 + 14124829.

It is an arithmetic number, because the mean of its divisors is an integer number (14124829).

Almost surely, 2^28249657 is an apocalyptic number.

It is an amenable number.

28249657 is a deficient number, since it is larger than the sum of its proper divisors (1).

28249657 is an equidigital number, since it uses as much as digits as its factorization.

28249657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 43.

The square root of 28249657 is about 5315.0406395436. The cubic root of 28249657 is about 304.5587348266.

The spelling of 28249657 in words is "twenty-eight million, two hundred forty-nine thousand, six hundred fifty-seven".