28628515 has 8 divisors (see below), whose sum is σ = 34489440. Its totient is φ = 22812672.

The previous prime is 28628503. The next prime is 28628519. The reversal of 28628515 is 51582682.

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

It is a cyclic number.

It is not a de Polignac number, because 28628515 - 2⁷ = 28628387 is a prime.

It is a super-2 number, since 2×28628515² = 1639183742210450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28628519) 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 7 ways as a sum of consecutive naturals, for example, 9855 + ... + 12424.

It is an arithmetic number, because the mean of its divisors is an integer number (4311180).

Almost surely, 2^28628515 is an apocalyptic number.

28628515 is a deficient number, since it is larger than the sum of its proper divisors (5860925).

28628515 is a wasteful number, since it uses less digits than its factorization.

28628515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22541.

The product of its digits is 38400, while the sum is 37.

The square root of 28628515 is about 5350.5621200020. The cubic root of 28628515 is about 305.9141791596.

The spelling of 28628515 in words is "twenty-eight million, six hundred twenty-eight thousand, five hundred fifteen".