28511551 has 2 divisors, whose sum is σ = 28511552. Its totient is φ = 28511550.

The previous prime is 28511531. The next prime is 28511591. The reversal of 28511551 is 15511582.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28511551 - 2¹⁷ = 28380479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28511521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14255775 + 14255776.

It is an arithmetic number, because the mean of its divisors is an integer number (14255776).

Almost surely, 2^28511551 is an apocalyptic number.

28511551 is a deficient number, since it is larger than the sum of its proper divisors (1).

28511551 is an equidigital number, since it uses as much as digits as its factorization.

28511551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2000, while the sum is 28.

The square root of 28511551 is about 5339.6208666908. The cubic root of 28511551 is about 305.4969985321.

The spelling of 28511551 in words is "twenty-eight million, five hundred eleven thousand, five hundred fifty-one".