13121230021 has 8 divisors (see below), whose sum is σ = 13339329984. Its totient is φ = 12904166880.

The previous prime is 13121230009. The next prime is 13121230063. The reversal of 13121230021 is 12003212131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13121230021 - 2⁹ = 13121229509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13121229977 and 13121230004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13121231021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 233665 + ... + 284326.

It is an arithmetic number, because the mean of its divisors is an integer number (1667416248).

Almost surely, 2^13121230021 is an apocalyptic number.

It is an amenable number.

13121230021 is a deficient number, since it is larger than the sum of its proper divisors (218099963).

13121230021 is an equidigital number, since it uses as much as digits as its factorization.

13121230021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518411.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 13121230021 its reverse (12003212131), we get a palindrome (25124442152).

The spelling of 13121230021 in words is "thirteen billion, one hundred twenty-one million, two hundred thirty thousand, twenty-one".