13784257 has 2 divisors, whose sum is σ = 13784258. Its totient is φ = 13784256.

The previous prime is 13784233. The next prime is 13784261. The reversal of 13784257 is 75248731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13278736 + 505521 = 3644^2 + 711^2 .

It is an emirp because it is prime and its reverse (75248731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13784257 - 2¹⁵ = 13751489 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13784227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6892128 + 6892129.

It is an arithmetic number, because the mean of its divisors is an integer number (6892129).

Almost surely, 2^13784257 is an apocalyptic number.

It is an amenable number.

13784257 is a deficient number, since it is larger than the sum of its proper divisors (1).

13784257 is an equidigital number, since it uses as much as digits as its factorization.

13784257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47040, while the sum is 37.

The square root of 13784257 is about 3712.7155829662. The cubic root of 13784257 is about 239.7697850288.

It can be divided in two parts, 13784 and 257, that added together give a palindrome (14041).

The spelling of 13784257 in words is "thirteen million, seven hundred eighty-four thousand, two hundred fifty-seven".