121109782890121 has 9 divisors (see below), whose sum is σ = 121300567898133. Its totient is φ = 120919297535520.

The previous prime is 121109782890097. The next prime is 121109782890199. The reversal of 121109782890121 is 121098287901121.

It is a happy number.

The square root of 121109782890121 is 11004989.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 38439863600121 + 82669919290000 = 6199989^2 + 9092300^2 .

It is not a de Polignac number, because 121109782890121 - 2³³ = 121101192955529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121109782891121) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 7274289405 + ... + 7274306053.

Almost surely, 2^{121109782890121} is an apocalyptic number.

121109782890121 is the 11004989-th square number.

121109782890121 is the 5502495-th centered octagonal number.

It is an amenable number.

121109782890121 is a deficient number, since it is larger than the sum of its proper divisors (190785008012).

121109782890121 is an frugal number, since it uses more digits than its factorization.

121109782890121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34620 (or 17310 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 52.

The spelling of 121109782890121 in words is "one hundred twenty-one trillion, one hundred nine billion, seven hundred eighty-two million, eight hundred ninety thousand, one hundred twenty-one".