28987769 has 2 divisors, whose sum is σ = 28987770. Its totient is φ = 28987768.

The previous prime is 28987747. The next prime is 28987781. The reversal of 28987769 is 96778982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27457600 + 1530169 = 5240^2 + 1237^2 .

It is a cyclic number.

It is not a de Polignac number, because 28987769 - 2⁸ = 28987513 is a prime.

It is a super-2 number, since 2×28987769² = 1680581503194722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28987799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14493884 + 14493885.

It is an arithmetic number, because the mean of its divisors is an integer number (14493885).

Almost surely, 2^28987769 is an apocalyptic number.

It is an amenable number.

28987769 is a deficient number, since it is larger than the sum of its proper divisors (1).

28987769 is an equidigital number, since it uses as much as digits as its factorization.

28987769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3048192, while the sum is 56.

The square root of 28987769 is about 5384.0290675293. The cubic root of 28987769 is about 307.1884839580.

The spelling of 28987769 in words is "twenty-eight million, nine hundred eighty-seven thousand, seven hundred sixty-nine".