21346305691 has 2 divisors, whose sum is σ = 21346305692. Its totient is φ = 21346305690.

The previous prime is 21346305653. The next prime is 21346305709. The reversal of 21346305691 is 19650364312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21346305691 - 2¹³ = 21346297499 is a prime.

It is not a weakly prime, because it can be changed into another prime (21346305091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10673152845 + 10673152846.

It is an arithmetic number, because the mean of its divisors is an integer number (10673152846).

Almost surely, 2^21346305691 is an apocalyptic number.

21346305691 is a deficient number, since it is larger than the sum of its proper divisors (1).

21346305691 is an equidigital number, since it uses as much as digits as its factorization.

21346305691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 116640, while the sum is 40.

The spelling of 21346305691 in words is "twenty-one billion, three hundred forty-six million, three hundred five thousand, six hundred ninety-one".