13727781 has 12 divisors (see below), whose sum is σ = 19880640. Its totient is φ = 9128040.

The previous prime is 13727773. The next prime is 13727783. The reversal of 13727781 is 18772731.

It is a happy number.

It is not a de Polignac number, because 13727781 - 2³ = 13727773 is a prime.

It is a super-2 number, since 2×13727781² = 376903942367922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13727783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2110 + ... + 5648.

It is an arithmetic number, because the mean of its divisors is an integer number (1656720).

Almost surely, 2^13727781 is an apocalyptic number.

It is an amenable number.

13727781 is a deficient number, since it is larger than the sum of its proper divisors (6152859).

13727781 is a wasteful number, since it uses less digits than its factorization.

13727781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3976 (or 3973 counting only the distinct ones).

The product of its digits is 16464, while the sum is 36.

The square root of 13727781 is about 3705.1020228868. The cubic root of 13727781 is about 239.4418801822.

The spelling of 13727781 in words is "thirteen million, seven hundred twenty-seven thousand, seven hundred eighty-one".