28451538 has 24 divisors (see below), whose sum is σ = 61820928. Its totient is φ = 9456792.

The previous prime is 28451519. The next prime is 28451539. The reversal of 28451538 is 83515482.

It is a happy number.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (28451539) 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 11 ways as a sum of consecutive naturals, for example, 4831 + ... + 8957.

It is an arithmetic number, because the mean of its divisors is an integer number (2575872).

Almost surely, 2^28451538 is an apocalyptic number.

28451538 is an abundant number, since it is smaller than the sum of its proper divisors (33369390).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28451538 is a wasteful number, since it uses less digits than its factorization.

28451538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4518 (or 4515 counting only the distinct ones).

The product of its digits is 38400, while the sum is 36.

The square root of 28451538 is about 5333.9983127106. The cubic root of 28451538 is about 305.2825045324.

The spelling of 28451538 in words is "twenty-eight million, four hundred fifty-one thousand, five hundred thirty-eight".