121210120211989 has 4 divisors (see below), whose sum is σ = 121592486522124. Its totient is φ = 120827753901856.

The previous prime is 121210120211969. The next prime is 121210120211993. The reversal of 121210120211989 is 989112021012121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 68970400644964 + 52239719567025 = 8304842^2 + 7227705^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121210120211989 is a prime.

It is a super-2 number, since 2×121210120211989² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121210120211969) 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, 191183154592 + ... + 191183155225.

It is an arithmetic number, because the mean of its divisors is an integer number (30398121630531).

Almost surely, 2^{121210120211989} is an apocalyptic number.

It is an amenable number.

121210120211989 is a deficient number, since it is larger than the sum of its proper divisors (382366310135).

121210120211989 is an equidigital number, since it uses as much as digits as its factorization.

121210120211989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382366310134.

The product of its (nonzero) digits is 10368, while the sum is 40.

The spelling of 121210120211989 in words is "one hundred twenty-one trillion, two hundred ten billion, one hundred twenty million, two hundred eleven thousand, nine hundred eighty-nine".