28663121 has 2 divisors, whose sum is σ = 28663122. Its totient is φ = 28663120.

The previous prime is 28663111. The next prime is 28663157. The reversal of 28663121 is 12136682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15054400 + 13608721 = 3880^2 + 3689^2 .

It is a cyclic number.

It is not a de Polignac number, because 28663121 - 2⁶ = 28663057 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28663111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14331560 + 14331561.

It is an arithmetic number, because the mean of its divisors is an integer number (14331561).

Almost surely, 2^28663121 is an apocalyptic number.

It is an amenable number.

28663121 is a deficient number, since it is larger than the sum of its proper divisors (1).

28663121 is an equidigital number, since it uses as much as digits as its factorization.

28663121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 29.

The square root of 28663121 is about 5353.7950091501. The cubic root of 28663121 is about 306.0373920160.

The spelling of 28663121 in words is "twenty-eight million, six hundred sixty-three thousand, one hundred twenty-one".