28676621 has 4 divisors (see below), whose sum is σ = 29665500. Its totient is φ = 27687744.

The previous prime is 28676617. The next prime is 28676629. The reversal of 28676621 is 12667682.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7645225 + 21031396 = 2765^2 + 4586^2 .

It is a cyclic number.

It is not a de Polignac number, because 28676621 - 2² = 28676617 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28676629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 494396 + ... + 494453.

It is an arithmetic number, because the mean of its divisors is an integer number (7416375).

Almost surely, 2^28676621 is an apocalyptic number.

It is an amenable number.

28676621 is a deficient number, since it is larger than the sum of its proper divisors (988879).

28676621 is an equidigital number, since it uses as much as digits as its factorization.

28676621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 988878.

The product of its digits is 48384, while the sum is 38.

The square root of 28676621 is about 5355.0556486371. The cubic root of 28676621 is about 306.0854311709.

The spelling of 28676621 in words is "twenty-eight million, six hundred seventy-six thousand, six hundred twenty-one".