28133501 has 16 divisors (see below), whose sum is σ = 31726080. Its totient is φ = 24728880.

The previous prime is 28133491. The next prime is 28133507. The reversal of 28133501 is 10533182.

28133501 = T₄₇₃ + T₄₇₄ + ... + T₆₄₉.

It is not a de Polignac number, because 28133501 - 2⁶ = 28133437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28133507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43160 + ... + 43806.

It is an arithmetic number, because the mean of its divisors is an integer number (1982880).

Almost surely, 2^28133501 is an apocalyptic number.

It is an amenable number.

28133501 is a deficient number, since it is larger than the sum of its proper divisors (3592579).

28133501 is a wasteful number, since it uses less digits than its factorization.

28133501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 784.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 28133501 is about 5304.1022803110. The cubic root of 28133501 is about 304.1407365731.

Adding to 28133501 its reverse (10533182), we get a palindrome (38666683).

The spelling of 28133501 in words is "twenty-eight million, one hundred thirty-three thousand, five hundred one".