28724451 has 8 divisors (see below), whose sum is σ = 43770624. Its totient is φ = 16413960.

The previous prime is 28724429. The next prime is 28724459. The reversal of 28724451 is 15442782.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28724451 - 2⁵ = 28724419 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28724459) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 683895 + ... + 683936.

It is an arithmetic number, because the mean of its divisors is an integer number (5471328).

Almost surely, 2^28724451 is an apocalyptic number.

28724451 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28724451 is a deficient number, since it is larger than the sum of its proper divisors (15046173).

28724451 is a wasteful number, since it uses less digits than its factorization.

28724451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1367841.

The product of its digits is 17920, while the sum is 33.

The square root of 28724451 is about 5359.5196613129. The cubic root of 28724451 is about 306.2555108824.

The spelling of 28724451 in words is "twenty-eight million, seven hundred twenty-four thousand, four hundred fifty-one".