13097821 has 16 divisors (see below), whose sum is σ = 15566400. Its totient is φ = 10886400.

The previous prime is 13097809. The next prime is 13097857. The reversal of 13097821 is 12879031.

It is a cyclic number.

It is not a de Polignac number, because 13097821 - 2²³ = 4709213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13097801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4981 + ... + 7141.

It is an arithmetic number, because the mean of its divisors is an integer number (972900).

Almost surely, 2^13097821 is an apocalyptic number.

13097821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13097821 is a deficient number, since it is larger than the sum of its proper divisors (2468579).

13097821 is a wasteful number, since it uses less digits than its factorization.

13097821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2220.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 13097821 is about 3619.0911842616. The cubic root of 13097821 is about 235.7217646497.

The spelling of 13097821 in words is "thirteen million, ninety-seven thousand, eight hundred twenty-one".