291542121 has 12 divisors (see below), whose sum is σ = 453510148. Its totient is φ = 179410464.

The previous prime is 291542093. The next prime is 291542123. The reversal of 291542121 is 121245192.

It can be written as a sum of positive squares in 2 ways, for example, as 122412096 + 169130025 = 11064^2 + 13005^2 .

It is not a de Polignac number, because 291542121 - 2⁶ = 291542057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (291542123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1245790 + ... + 1246023.

Almost surely, 2^291542121 is an apocalyptic number.

It is an amenable number.

291542121 is a deficient number, since it is larger than the sum of its proper divisors (161968027).

291542121 is a wasteful number, since it uses less digits than its factorization.

291542121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2491832 (or 2491829 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 291542121 is about 17074.6045635031. The cubic root of 291542121 is about 663.0817927659.

The spelling of 291542121 in words is "two hundred ninety-one million, five hundred forty-two thousand, one hundred twenty-one".