28408451 has 4 divisors (see below), whose sum is σ = 28461504. Its totient is φ = 28355400.

The previous prime is 28408447. The next prime is 28408453. The reversal of 28408451 is 15480482.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28408451 - 2² = 28408447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28408453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25715 + ... + 26796.

It is an arithmetic number, because the mean of its divisors is an integer number (7115376).

Almost surely, 2^28408451 is an apocalyptic number.

28408451 is a deficient number, since it is larger than the sum of its proper divisors (53053).

28408451 is an equidigital number, since it uses as much as digits as its factorization.

28408451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53052.

The product of its (nonzero) digits is 10240, while the sum is 32.

The square root of 28408451 is about 5329.9578797585. The cubic root of 28408451 is about 305.1283200984.

The spelling of 28408451 in words is "twenty-eight million, four hundred eight thousand, four hundred fifty-one".