28771819 has 2 divisors, whose sum is σ = 28771820. Its totient is φ = 28771818.

The previous prime is 28771817. The next prime is 28771889. The reversal of 28771819 is 91817782.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28771819 - 2¹ = 28771817 is a prime.

It is a super-2 number, since 2×28771819² = 1655635137137522, which contains 22 as substring.

Together with 28771817, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28771811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14385909 + 14385910.

It is an arithmetic number, because the mean of its divisors is an integer number (14385910).

Almost surely, 2^28771819 is an apocalyptic number.

28771819 is a deficient number, since it is larger than the sum of its proper divisors (1).

28771819 is an equidigital number, since it uses as much as digits as its factorization.

28771819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56448, while the sum is 43.

The square root of 28771819 is about 5363.9368937377. The cubic root of 28771819 is about 306.4237617830.

The spelling of 28771819 in words is "twenty-eight million, seven hundred seventy-one thousand, eight hundred nineteen".