28215845 has 16 divisors (see below), whose sum is σ = 39099648. Its totient is φ = 19146240.

The previous prime is 28215809. The next prime is 28215851. The reversal of 28215845 is 54851282.

It is a happy number.

It is not a de Polignac number, because 28215845 - 2¹⁰ = 28214821 is a prime.

It is a super-2 number, since 2×28215845² = 1592267818128050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 761 + ... + 7550.

It is an arithmetic number, because the mean of its divisors is an integer number (2443728).

Almost surely, 2^28215845 is an apocalyptic number.

It is an amenable number.

28215845 is a deficient number, since it is larger than the sum of its proper divisors (10883803).

28215845 is an equidigital number, since it uses as much as digits as its factorization.

28215845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8420.

The product of its digits is 25600, while the sum is 35.

The square root of 28215845 is about 5311.8589024936. The cubic root of 28215845 is about 304.4371775852.

The spelling of 28215845 in words is "twenty-eight million, two hundred fifteen thousand, eight hundred forty-five".