28893881 has 2 divisors, whose sum is σ = 28893882. Its totient is φ = 28893880.

The previous prime is 28893859. The next prime is 28893899. The reversal of 28893881 is 18839882.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19536400 + 9357481 = 4420^2 + 3059^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28893881 is a prime.

It is a super-2 number, since 2×28893881² = 1669712718484322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28893811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14446940 + 14446941.

It is an arithmetic number, because the mean of its divisors is an integer number (14446941).

Almost surely, 2^28893881 is an apocalyptic number.

It is an amenable number.

28893881 is a deficient number, since it is larger than the sum of its proper divisors (1).

28893881 is an equidigital number, since it uses as much as digits as its factorization.

28893881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 221184, while the sum is 47.

The square root of 28893881 is about 5375.3028751876. The cubic root of 28893881 is about 306.8564760410.

The spelling of 28893881 in words is "twenty-eight million, eight hundred ninety-three thousand, eight hundred eighty-one".