291949139 has 2 divisors, whose sum is σ = 291949140. Its totient is φ = 291949138.

The previous prime is 291949121. The next prime is 291949153. The reversal of 291949139 is 931949192.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 291949139 - 2²⁰ = 290900563 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 291949093 and 291949102.

It is not a weakly prime, because it can be changed into another prime (291949439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145974569 + 145974570.

It is an arithmetic number, because the mean of its divisors is an integer number (145974570).

Almost surely, 2^291949139 is an apocalyptic number.

291949139 is a deficient number, since it is larger than the sum of its proper divisors (1).

291949139 is an equidigital number, since it uses as much as digits as its factorization.

291949139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 157464, while the sum is 47.

The square root of 291949139 is about 17086.5192183780. The cubic root of 291949139 is about 663.3902224440.

The spelling of 291949139 in words is "two hundred ninety-one million, nine hundred forty-nine thousand, one hundred thirty-nine".