28691629 has 2 divisors, whose sum is σ = 28691630. Its totient is φ = 28691628.

The previous prime is 28691617. The next prime is 28691633. The reversal of 28691629 is 92619682.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17867529 + 10824100 = 4227^2 + 3290^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28691629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28691609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14345814 + 14345815.

It is an arithmetic number, because the mean of its divisors is an integer number (14345815).

Almost surely, 2^28691629 is an apocalyptic number.

It is an amenable number.

28691629 is a deficient number, since it is larger than the sum of its proper divisors (1).

28691629 is an equidigital number, since it uses as much as digits as its factorization.

28691629 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 43.

The square root of 28691629 is about 5356.4567579698. The cubic root of 28691629 is about 306.1388187836.

The spelling of 28691629 in words is "twenty-eight million, six hundred ninety-one thousand, six hundred twenty-nine".