21311824403959 has 2 divisors, whose sum is σ = 21311824403960. Its totient is φ = 21311824403958.

The previous prime is 21311824403953. The next prime is 21311824404023. The reversal of 21311824403959 is 95930442811312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21311824403959 - 2¹¹ = 21311824401911 is a prime.

It is a super-2 number, since 2×21311824403959² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21311824403953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655912201979 + 10655912201980.

It is an arithmetic number, because the mean of its divisors is an integer number (10655912201980).

Almost surely, 2^{21311824403959} is an apocalyptic number.

21311824403959 is a deficient number, since it is larger than the sum of its proper divisors (1).

21311824403959 is an equidigital number, since it uses as much as digits as its factorization.

21311824403959 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1866240, while the sum is 52.

The spelling of 21311824403959 in words is "twenty-one trillion, three hundred eleven billion, eight hundred twenty-four million, four hundred three thousand, nine hundred fifty-nine".