13640281 has 4 divisors (see below), whose sum is σ = 13651200. Its totient is φ = 13629364.

The previous prime is 13640267. The next prime is 13640287. The reversal of 13640281 is 18204631.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18204631 = 587 ⋅31013.

It is a cyclic number.

It is not a de Polignac number, because 13640281 - 2⁷ = 13640153 is a prime.

It is a super-2 number, since 2×13640281² = 372114531517922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13640287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3301 + ... + 6178.

It is an arithmetic number, because the mean of its divisors is an integer number (3412800).

Almost surely, 2^13640281 is an apocalyptic number.

It is an amenable number.

13640281 is a deficient number, since it is larger than the sum of its proper divisors (10919).

13640281 is an equidigital number, since it uses as much as digits as its factorization.

13640281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10918.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 13640281 is about 3693.2751048358. The cubic root of 13640281 is about 238.9320663817.

The spelling of 13640281 in words is "thirteen million, six hundred forty thousand, two hundred eighty-one".