28855621 has 2 divisors, whose sum is σ = 28855622. Its totient is φ = 28855620.

The previous prime is 28855577. The next prime is 28855649. The reversal of 28855621 is 12655882.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17892900 + 10962721 = 4230^2 + 3311^2 .

It is a cyclic number.

It is not a de Polignac number, because 28855621 - 2¹⁵ = 28822853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28853621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14427810 + 14427811.

It is an arithmetic number, because the mean of its divisors is an integer number (14427811).

Almost surely, 2^28855621 is an apocalyptic number.

It is an amenable number.

28855621 is a deficient number, since it is larger than the sum of its proper divisors (1).

28855621 is an equidigital number, since it uses as much as digits as its factorization.

28855621 is an evil number, because the sum of its binary digits is even.

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

The square root of 28855621 is about 5371.7428270534. The cubic root of 28855621 is about 306.7209742878.

The spelling of 28855621 in words is "twenty-eight million, eight hundred fifty-five thousand, six hundred twenty-one".