28726661 has 2 divisors, whose sum is σ = 28726662. Its totient is φ = 28726660.

The previous prime is 28726657. The next prime is 28726667. The reversal of 28726661 is 16662782.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24750625 + 3976036 = 4975^2 + 1994^2 .

It is a cyclic number.

It is not a de Polignac number, because 28726661 - 2² = 28726657 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 (28726667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14363330 + 14363331.

It is an arithmetic number, because the mean of its divisors is an integer number (14363331).

Almost surely, 2^28726661 is an apocalyptic number.

It is an amenable number.

28726661 is a deficient number, since it is larger than the sum of its proper divisors (1).

28726661 is an equidigital number, since it uses as much as digits as its factorization.

28726661 is an odious number, because the sum of its binary digits is odd.

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

The square root of 28726661 is about 5359.7258325403. The cubic root of 28726661 is about 306.2633649033.

The spelling of 28726661 in words is "twenty-eight million, seven hundred twenty-six thousand, six hundred sixty-one".