13121123100021 has 16 divisors (see below), whose sum is σ = 19441231947520. Its totient is φ = 8746276423680.

The previous prime is 13121123099983. The next prime is 13121123100053. The reversal of 13121123100021 is 12000132112131.

It is not a de Polignac number, because 13121123100021 - 2⁶ = 13121123099957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13121123099967 and 13121123100003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13121123100721) 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, 31427005 + ... + 31841778.

It is an arithmetic number, because the mean of its divisors is an integer number (1215076996720).

Almost surely, 2^{13121123100021} is an apocalyptic number.

It is an amenable number.

13121123100021 is a deficient number, since it is larger than the sum of its proper divisors (6320108847499).

13121123100021 is an equidigital number, since it uses as much as digits as its factorization.

13121123100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63276473 (or 63276467 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 13121123100021 its reverse (12000132112131), we get a palindrome (25121255212152).

The spelling of 13121123100021 in words is "thirteen trillion, one hundred twenty-one billion, one hundred twenty-three million, one hundred thousand, twenty-one".