28636993 has 32 divisors (see below), whose sum is σ = 38320128. Its totient is φ = 20716800.

The previous prime is 28636967. The next prime is 28636997. The reversal of 28636993 is 39963682.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 28636993 - 2⁵ = 28636961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28636997) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 171396 + ... + 171562.

It is an arithmetic number, because the mean of its divisors is an integer number (1197504).

Almost surely, 2^28636993 is an apocalyptic number.

It is an amenable number.

28636993 is a deficient number, since it is larger than the sum of its proper divisors (9683135).

28636993 is a wasteful number, since it uses less digits than its factorization.

28636993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333.

The product of its digits is 419904, while the sum is 46.

The square root of 28636993 is about 5351.3543145637. The cubic root of 28636993 is about 305.9443738150.

The spelling of 28636993 in words is "twenty-eight million, six hundred thirty-six thousand, nine hundred ninety-three".