28291215 has 8 divisors (see below), whose sum is σ = 45265968. Its totient is φ = 15088640.

The previous prime is 28291187. The next prime is 28291217. The reversal of 28291215 is 51219282.

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

It is not a de Polignac number, because 28291215 - 2⁵ = 28291183 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28291217) 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, 943026 + ... + 943055.

It is an arithmetic number, because the mean of its divisors is an integer number (5658246).

Almost surely, 2^28291215 is an apocalyptic number.

28291215 is a deficient number, since it is larger than the sum of its proper divisors (16974753).

28291215 is a wasteful number, since it uses less digits than its factorization.

28291215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1886089.

The product of its digits is 2880, while the sum is 30.

The square root of 28291215 is about 5318.9486743153. The cubic root of 28291215 is about 304.7080068512.

The spelling of 28291215 in words is "twenty-eight million, two hundred ninety-one thousand, two hundred fifteen".