13214781 has 12 divisors (see below), whose sum is σ = 19149052. Its totient is φ = 8781696.

The previous prime is 13214777. The next prime is 13214783. The reversal of 13214781 is 18741231.

13214781 is digitally balanced in base 2, base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 9865881 + 3348900 = 3141^2 + 1830^2 .

It is not a de Polignac number, because 13214781 - 2² = 13214777 is a prime.

It is a super-2 number, since 2×13214781² = 349260873755922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13214783) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 855 + ... + 5211.

Almost surely, 2^13214781 is an apocalyptic number.

It is an amenable number.

13214781 is a deficient number, since it is larger than the sum of its proper divisors (5934271).

13214781 is a wasteful number, since it uses less digits than its factorization.

13214781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4700 (or 4697 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 13214781 is about 3635.2140239606. The cubic root of 13214781 is about 236.4213303264.

The spelling of 13214781 in words is "thirteen million, two hundred fourteen thousand, seven hundred eighty-one".