121201023420021 has 4 divisors (see below), whose sum is σ = 161601364560032. Its totient is φ = 80800682280012.

The previous prime is 121201023419981. The next prime is 121201023420023. The reversal of 121201023420021 is 120024320102121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 121201023420021 - 2⁷ = 121201023419893 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121201023420021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121201023420023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20200170570001 + ... + 20200170570006.

It is an arithmetic number, because the mean of its divisors is an integer number (40400341140008).

Almost surely, 2^{121201023420021} is an apocalyptic number.

It is an amenable number.

121201023420021 is a deficient number, since it is larger than the sum of its proper divisors (40400341140011).

121201023420021 is an equidigital number, since it uses as much as digits as its factorization.

121201023420021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40400341140010.

The product of its (nonzero) digits is 384, while the sum is 21.

Adding to 121201023420021 its reverse (120024320102121), we get a palindrome (241225343522142).

The spelling of 121201023420021 in words is "one hundred twenty-one trillion, two hundred one billion, twenty-three million, four hundred twenty thousand, twenty-one".