21865424600431 has 2 divisors, whose sum is σ = 21865424600432. Its totient is φ = 21865424600430.

The previous prime is 21865424600429. The next prime is 21865424600443. The reversal of 21865424600431 is 13400642456812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21865424600431 - 2¹ = 21865424600429 is a prime.

It is a super-2 number, since 2×21865424600431² (a number of 27 digits) contains 22 as substring.

Together with 21865424600429, 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 (21865424607431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10932712300215 + 10932712300216.

It is an arithmetic number, because the mean of its divisors is an integer number (10932712300216).

Almost surely, 2^{21865424600431} is an apocalyptic number.

21865424600431 is a deficient number, since it is larger than the sum of its proper divisors (1).

21865424600431 is an equidigital number, since it uses as much as digits as its factorization.

21865424600431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1105920, while the sum is 46.

The spelling of 21865424600431 in words is "twenty-one trillion, eight hundred sixty-five billion, four hundred twenty-four million, six hundred thousand, four hundred thirty-one".