28240357 has 2 divisors, whose sum is σ = 28240358. Its totient is φ = 28240356.

The previous prime is 28240337. The next prime is 28240391. The reversal of 28240357 is 75304282.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23338561 + 4901796 = 4831^2 + 2214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28240357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28240337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14120178 + 14120179.

It is an arithmetic number, because the mean of its divisors is an integer number (14120179).

Almost surely, 2^28240357 is an apocalyptic number.

It is an amenable number.

28240357 is a deficient number, since it is larger than the sum of its proper divisors (1).

28240357 is an equidigital number, since it uses as much as digits as its factorization.

28240357 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13440, while the sum is 31.

The square root of 28240357 is about 5314.1656918090. The cubic root of 28240357 is about 304.5253101482.

The spelling of 28240357 in words is "twenty-eight million, two hundred forty thousand, three hundred fifty-seven".