291000421 has 2 divisors, whose sum is σ = 291000422. Its totient is φ = 291000420.

The previous prime is 291000419. The next prime is 291000473. The reversal of 291000421 is 124000192.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 256320100 + 34680321 = 16010^2 + 5889^2 .

It is a cyclic number.

It is not a de Polignac number, because 291000421 - 2¹ = 291000419 is a prime.

Together with 291000419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (291000401) 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 as a sum of consecutive naturals, namely, 145500210 + 145500211.

It is an arithmetic number, because the mean of its divisors is an integer number (145500211).

Almost surely, 2^291000421 is an apocalyptic number.

It is an amenable number.

291000421 is a deficient number, since it is larger than the sum of its proper divisors (1).

291000421 is an equidigital number, since it uses as much as digits as its factorization.

291000421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 291000421 is about 17058.7344489561. The cubic root of 291000421 is about 662.6708583172.

The spelling of 291000421 in words is "two hundred ninety-one million, four hundred twenty-one", and thus it is an aban number.