121121221985 has 4 divisors (see below), whose sum is σ = 145345466388. Its totient is φ = 96896977584.

The previous prime is 121121221951. The next prime is 121121221987. The reversal of 121121221985 is 589122121121.

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 32930635024 + 88190586961 = 181468^2 + 296969^2 .

It is a cyclic number.

It is not a de Polignac number, because 121121221985 - 2⁸ = 121121221729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121121221987) 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, 12112122194 + ... + 12112122203.

It is an arithmetic number, because the mean of its divisors is an integer number (36336366597).

Almost surely, 2^121121221985 is an apocalyptic number.

It is an amenable number.

121121221985 is a deficient number, since it is larger than the sum of its proper divisors (24224244403).

121121221985 is an equidigital number, since it uses as much as digits as its factorization.

121121221985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24224244402.

The product of its digits is 5760, while the sum is 35.

The spelling of 121121221985 in words is "one hundred twenty-one billion, one hundred twenty-one million, two hundred twenty-one thousand, nine hundred eighty-five".