21816149423 has 2 divisors, whose sum is σ = 21816149424. Its totient is φ = 21816149422.

The previous prime is 21816149401. The next prime is 21816149473. The reversal of 21816149423 is 32494161812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21816149423 - 2³⁰ = 20742407599 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21816149473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10908074711 + 10908074712.

It is an arithmetic number, because the mean of its divisors is an integer number (10908074712).

Almost surely, 2^21816149423 is an apocalyptic number.

21816149423 is a deficient number, since it is larger than the sum of its proper divisors (1).

21816149423 is an equidigital number, since it uses as much as digits as its factorization.

21816149423 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 82944, while the sum is 41.

The spelling of 21816149423 in words is "twenty-one billion, eight hundred sixteen million, one hundred forty-nine thousand, four hundred twenty-three".