13772809 has 2 divisors, whose sum is σ = 13772810. Its totient is φ = 13772808.

The previous prime is 13772753. The next prime is 13772821. The reversal of 13772809 is 90827731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11923209 + 1849600 = 3453^2 + 1360^2 .

It is a cyclic number.

It is not a de Polignac number, because 13772809 - 2¹¹ = 13770761 is a prime.

It is not a weakly prime, because it can be changed into another prime (13772879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6886404 + 6886405.

It is an arithmetic number, because the mean of its divisors is an integer number (6886405).

Almost surely, 2^13772809 is an apocalyptic number.

It is an amenable number.

13772809 is a deficient number, since it is larger than the sum of its proper divisors (1).

13772809 is an equidigital number, since it uses as much as digits as its factorization.

13772809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 13772809 is about 3711.1735340725. The cubic root of 13772809 is about 239.7033893636.

It can be divided in two parts, 1377 and 2809, that added together give a triangular number (4186 = T₉₁).

The spelling of 13772809 in words is "thirteen million, seven hundred seventy-two thousand, eight hundred nine".