21111434310391 has 2 divisors, whose sum is σ = 21111434310392. Its totient is φ = 21111434310390.

The previous prime is 21111434310389. The next prime is 21111434310433. The reversal of 21111434310391 is 19301343411112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21111434310391 - 2¹ = 21111434310389 is a prime.

Together with 21111434310389, 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 (21111434310301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555717155195 + 10555717155196.

It is an arithmetic number, because the mean of its divisors is an integer number (10555717155196).

Almost surely, 2^{21111434310391} is an apocalyptic number.

21111434310391 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111434310391 is an equidigital number, since it uses as much as digits as its factorization.

21111434310391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 34.

The spelling of 21111434310391 in words is "twenty-one trillion, one hundred eleven billion, four hundred thirty-four million, three hundred ten thousand, three hundred ninety-one".