28321655 has 8 divisors (see below), whose sum is σ = 34137072. Its totient is φ = 22556608.

The previous prime is 28321651. The next prime is 28321679. The reversal of 28321655 is 55612382.

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 28321655 - 2² = 28321651 is a prime.

It is a super-2 number, since 2×28321655² = 1604232283878050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28321651) 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, 11342 + ... + 13611.

It is an arithmetic number, because the mean of its divisors is an integer number (4267134).

Almost surely, 2^28321655 is an apocalyptic number.

28321655 is a deficient number, since it is larger than the sum of its proper divisors (5815417).

28321655 is a wasteful number, since it uses less digits than its factorization.

28321655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25185.

The product of its digits is 14400, while the sum is 32.

The square root of 28321655 is about 5321.8093727604. The cubic root of 28321655 is about 304.8172514479.

The spelling of 28321655 in words is "twenty-eight million, three hundred twenty-one thousand, six hundred fifty-five".