28308551 has 2 divisors, whose sum is σ = 28308552. Its totient is φ = 28308550.

The previous prime is 28308529. The next prime is 28308557. The reversal of 28308551 is 15580382.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28308551 - 2¹⁰ = 28307527 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28308557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14154275 + 14154276.

It is an arithmetic number, because the mean of its divisors is an integer number (14154276).

Almost surely, 2^28308551 is an apocalyptic number.

28308551 is a deficient number, since it is larger than the sum of its proper divisors (1).

28308551 is an equidigital number, since it uses as much as digits as its factorization.

28308551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9600, while the sum is 32.

The square root of 28308551 is about 5320.5780700973. The cubic root of 28308551 is about 304.7702327566.

The spelling of 28308551 in words is "twenty-eight million, three hundred eight thousand, five hundred fifty-one".