28724415 has 8 divisors (see below), whose sum is σ = 45959088. Its totient is φ = 15319680.

The previous prime is 28724363. The next prime is 28724419. The reversal of 28724415 is 51442782.

28724415 is nontrivially palindromic in base 13.

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

It is not a de Polignac number, because 28724415 - 2⁸ = 28724159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28724419) 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, 957466 + ... + 957495.

It is an arithmetic number, because the mean of its divisors is an integer number (5744886).

Almost surely, 2^28724415 is an apocalyptic number.

28724415 is a deficient number, since it is larger than the sum of its proper divisors (17234673).

28724415 is a wasteful number, since it uses less digits than its factorization.

28724415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1914969.

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

The square root of 28724415 is about 5359.5163028020. The cubic root of 28724415 is about 306.2553829402.

The spelling of 28724415 in words is "twenty-eight million, seven hundred twenty-four thousand, four hundred fifteen".