28691219 has 2 divisors, whose sum is σ = 28691220. Its totient is φ = 28691218.

The previous prime is 28691207. The next prime is 28691261. The reversal of 28691219 is 91219682.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28691219 - 2¹² = 28687123 is a prime.

It is a super-2 number, since 2×28691219² = 1646372095411922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28697219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14345609 + 14345610.

It is an arithmetic number, because the mean of its divisors is an integer number (14345610).

Almost surely, 2^28691219 is an apocalyptic number.

28691219 is a deficient number, since it is larger than the sum of its proper divisors (1).

28691219 is an equidigital number, since it uses as much as digits as its factorization.

28691219 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 38.

The square root of 28691219 is about 5356.4184862649. The cubic root of 28691219 is about 306.1373605474.

The spelling of 28691219 in words is "twenty-eight million, six hundred ninety-one thousand, two hundred nineteen".