121242881 has 4 divisors (see below), whose sum is σ = 125423700. Its totient is φ = 117062064.

The previous prime is 121242871. The next prime is 121242899. The reversal of 121242881 is 188242121.

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 100000000 + 21242881 = 10000^2 + 4609^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121242881 is a prime.

It is a super-2 number, since 2×121242881² = 29399672386360322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 4180789 = 121242881 / (1 + 2 + 1 + 2 + 4 + 2 + 8 + 8 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121242811) 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, 2090366 + ... + 2090423.

It is an arithmetic number, because the mean of its divisors is an integer number (31355925).

Almost surely, 2^121242881 is an apocalyptic number.

It is an amenable number.

121242881 is a deficient number, since it is larger than the sum of its proper divisors (4180819).

121242881 is an equidigital number, since it uses as much as digits as its factorization.

121242881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4180818.

The product of its digits is 2048, while the sum is 29.

The square root of 121242881 is about 11011.0345108895. The cubic root of 121242881 is about 494.9394627188.

The spelling of 121242881 in words is "one hundred twenty-one million, two hundred forty-two thousand, eight hundred eighty-one".