28640133 has 6 divisors (see below), whose sum is σ = 41369094. Its totient is φ = 19093416.

The previous prime is 28640119. The next prime is 28640147. The reversal of 28640133 is 33104682.

It is a happy number.

28640133 is a `hidden beast` number, since 2 + 8 + 640 + 13 + 3 = 666.

It is an interprime number because it is at equal distance from previous prime (28640119) and next prime (28640147).

It can be written as a sum of positive squares in only one way, i.e., 28227969 + 412164 = 5313^2 + 642^2 .

It is not a de Polignac number, because 28640133 - 2⁶ = 28640069 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28640097 and 28640106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28640033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1591110 + ... + 1591127.

It is an arithmetic number, because the mean of its divisors is an integer number (6894849).

Almost surely, 2^28640133 is an apocalyptic number.

It is an amenable number.

28640133 is a deficient number, since it is larger than the sum of its proper divisors (12728961).

28640133 is a wasteful number, since it uses less digits than its factorization.

28640133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3182243 (or 3182240 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 28640133 is about 5351.6476901979. The cubic root of 28640133 is about 305.9555555084.

The spelling of 28640133 in words is "twenty-eight million, six hundred forty thousand, one hundred thirty-three".