28215726 has 64 divisors (see below), whose sum is σ = 70986240. Its totient is φ = 7263360.

The previous prime is 28215713. The next prime is 28215727. The reversal of 28215726 is 62751282.

It is a super-2 number, since 2×28215726² = 1592254387414152, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28215727) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 72340 + ... + 72728.

It is an arithmetic number, because the mean of its divisors is an integer number (1109160).

Almost surely, 2^28215726 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28215726, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35493120).

28215726 is an abundant number, since it is smaller than the sum of its proper divisors (42770514).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28215726 is a wasteful number, since it uses less digits than its factorization.

28215726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569.

The product of its digits is 13440, while the sum is 33.

The square root of 28215726 is about 5311.8477011300. The cubic root of 28215726 is about 304.4367495978.

The spelling of 28215726 in words is "twenty-eight million, two hundred fifteen thousand, seven hundred twenty-six".