121001210021 has 4 divisors (see below), whose sum is σ = 121438037772. Its totient is φ = 120564382272.

The previous prime is 121001210017. The next prime is 121001210023. The reversal of 121001210021 is 120012100121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120012100121 = 56477 ⋅2124973.

It can be written as a sum of positive squares in 2 ways, for example, as 8061525796 + 112939684225 = 89786^2 + 336065^2 .

It is a cyclic number.

It is not a de Polignac number, because 121001210021 - 2² = 121001210017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121001209984 and 121001210011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121001210023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218413460 + ... + 218414013.

It is an arithmetic number, because the mean of its divisors is an integer number (30359509443).

Almost surely, 2^121001210021 is an apocalyptic number.

It is an amenable number.

121001210021 is a deficient number, since it is larger than the sum of its proper divisors (436827751).

121001210021 is an equidigital number, since it uses as much as digits as its factorization.

121001210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436827750.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 121001210021 its reverse (120012100121), we get a palindrome (241013310142).

The spelling of 121001210021 in words is "one hundred twenty-one billion, one million, two hundred ten thousand, twenty-one".