21342000391 has 2 divisors, whose sum is σ = 21342000392. Its totient is φ = 21342000390.

The previous prime is 21342000389. The next prime is 21342000419. The reversal of 21342000391 is 19300024312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21342000391 - 2¹ = 21342000389 is a prime.

Together with 21342000389, 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 (21342000301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671000195 + 10671000196.

It is an arithmetic number, because the mean of its divisors is an integer number (10671000196).

Almost surely, 2^21342000391 is an apocalyptic number.

21342000391 is a deficient number, since it is larger than the sum of its proper divisors (1).

21342000391 is an equidigital number, since it uses as much as digits as its factorization.

21342000391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

The spelling of 21342000391 in words is "twenty-one billion, three hundred forty-two million, three hundred ninety-one", and thus it is an aban number.