13020021 has 20 divisors (see below), whose sum is σ = 22229152. Its totient is φ = 7439688.

The previous prime is 13020017. The next prime is 13020037. The reversal of 13020021 is 12002031.

It is a happy number.

It is not a de Polignac number, because 13020021 - 2² = 13020017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13019985 and 13020012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13020071) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 10915 + ... + 12048.

Almost surely, 2^13020021 is an apocalyptic number.

It is an amenable number.

13020021 is a deficient number, since it is larger than the sum of its proper divisors (9209131).

13020021 is an equidigital number, since it uses as much as digits as its factorization.

13020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22982 (or 22973 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 13020021 is about 3608.3266204710. The cubic root of 13020021 is about 235.2541147349.

Adding to 13020021 its reverse (12002031), we get a palindrome (25022052).

The spelling of 13020021 in words is "thirteen million, twenty thousand, twenty-one".