28930621 has 2 divisors, whose sum is σ = 28930622. Its totient is φ = 28930620.

The previous prime is 28930613. The next prime is 28930631. The reversal of 28930621 is 12603982.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24393721 + 4536900 = 4939^2 + 2130^2 .

It is a cyclic number.

It is not a de Polignac number, because 28930621 - 2³ = 28930613 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28930631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14465310 + 14465311.

It is an arithmetic number, because the mean of its divisors is an integer number (14465311).

Almost surely, 2^28930621 is an apocalyptic number.

It is an amenable number.

28930621 is a deficient number, since it is larger than the sum of its proper divisors (1).

28930621 is an equidigital number, since it uses as much as digits as its factorization.

28930621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 28930621 is about 5378.7192713508. The cubic root of 28930621 is about 306.9864820200.

The spelling of 28930621 in words is "twenty-eight million, nine hundred thirty thousand, six hundred twenty-one".