13873781 has 4 divisors (see below), whose sum is σ = 14604000. Its totient is φ = 13143564.

The previous prime is 13873763. The next prime is 13873787. The reversal of 13873781 is 18737831.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13873781 is a prime.

It is a super-2 number, since 2×13873781² = 384963598471922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13873787) 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, 365081 + ... + 365118.

It is an arithmetic number, because the mean of its divisors is an integer number (3651000).

Almost surely, 2^13873781 is an apocalyptic number.

It is an amenable number.

13873781 is a deficient number, since it is larger than the sum of its proper divisors (730219).

13873781 is an equidigital number, since it uses as much as digits as its factorization.

13873781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 730218.

The product of its digits is 28224, while the sum is 38.

The square root of 13873781 is about 3724.7524749975. The cubic root of 13873781 is about 240.2877393781.

The spelling of 13873781 in words is "thirteen million, eight hundred seventy-three thousand, seven hundred eighty-one".