21043401427 has 2 divisors, whose sum is σ = 21043401428. Its totient is φ = 21043401426.

The previous prime is 21043401343. The next prime is 21043401437. The reversal of 21043401427 is 72410434012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21043401427 - 2¹⁵ = 21043368659 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21043401395 and 21043401404.

It is not a weakly prime, because it can be changed into another prime (21043401437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10521700713 + 10521700714.

It is an arithmetic number, because the mean of its divisors is an integer number (10521700714).

Almost surely, 2^21043401427 is an apocalyptic number.

21043401427 is a deficient number, since it is larger than the sum of its proper divisors (1).

21043401427 is an equidigital number, since it uses as much as digits as its factorization.

21043401427 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 28.

Adding to 21043401427 its reverse (72410434012), we get a palindrome (93453835439).

It can be divided in two parts, 21043401 and 427, that added together give a triangular number (21043828 = T₆₄₈₇).

The spelling of 21043401427 in words is "twenty-one billion, forty-three million, four hundred one thousand, four hundred twenty-seven".