13723821 has 12 divisors (see below), whose sum is σ = 19891872. Its totient is φ = 9117576.

The previous prime is 13723819. The next prime is 13723867. The reversal of 13723821 is 12832731.

13723821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 13723821 - 2¹ = 13723819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13723891) 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, 280 + ... + 5246.

It is an arithmetic number, because the mean of its divisors is an integer number (1657656).

Almost surely, 2^13723821 is an apocalyptic number.

It is an amenable number.

13723821 is a deficient number, since it is larger than the sum of its proper divisors (6168051).

13723821 is a wasteful number, since it uses less digits than its factorization.

13723821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5280 (or 5277 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 13723821 is about 3704.5675861023. The cubic root of 13723821 is about 239.4188543430.

The spelling of 13723821 in words is "thirteen million, seven hundred twenty-three thousand, eight hundred twenty-one".