28693993 has 2 divisors, whose sum is σ = 28693994. Its totient is φ = 28693992.

The previous prime is 28693957. The next prime is 28694027. The reversal of 28693993 is 39939682.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18215824 + 10478169 = 4268^2 + 3237^2 .

It is a cyclic number.

It is not a de Polignac number, because 28693993 - 2¹⁷ = 28562921 is a prime.

It is not a weakly prime, because it can be changed into another prime (28693493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14346996 + 14346997.

It is an arithmetic number, because the mean of its divisors is an integer number (14346997).

Almost surely, 2^28693993 is an apocalyptic number.

It is an amenable number.

28693993 is a deficient number, since it is larger than the sum of its proper divisors (1).

28693993 is an equidigital number, since it uses as much as digits as its factorization.

28693993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 629856, while the sum is 49.

The square root of 28693993 is about 5356.6774216859. The cubic root of 28693993 is about 306.1472264890.

The spelling of 28693993 in words is "twenty-eight million, six hundred ninety-three thousand, nine hundred ninety-three".