28643669 has 2 divisors, whose sum is σ = 28643670. Its totient is φ = 28643668.

The previous prime is 28643653. The next prime is 28643687. The reversal of 28643669 is 96634682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23522500 + 5121169 = 4850^2 + 2263^2 .

It is a cyclic number.

It is not a de Polignac number, because 28643669 - 2⁴ = 28643653 is a prime.

It is a super-2 number, since 2×28643669² = 1640919547563122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28643609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14321834 + 14321835.

It is an arithmetic number, because the mean of its divisors is an integer number (14321835).

Almost surely, 2^28643669 is an apocalyptic number.

It is an amenable number.

28643669 is a deficient number, since it is larger than the sum of its proper divisors (1).

28643669 is an equidigital number, since it uses as much as digits as its factorization.

28643669 is an evil number, because the sum of its binary digits is even.

The product of its digits is 373248, while the sum is 44.

The square root of 28643669 is about 5351.9780455454. The cubic root of 28643669 is about 305.9681463988.

The spelling of 28643669 in words is "twenty-eight million, six hundred forty-three thousand, six hundred sixty-nine".