21144315427 has 2 divisors, whose sum is σ = 21144315428. Its totient is φ = 21144315426.

The previous prime is 21144315377. The next prime is 21144315469. The reversal of 21144315427 is 72451344112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21144315427 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21144315392 and 21144315401.

It is not a weakly prime, because it can be changed into another prime (21144310427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10572157713 + 10572157714.

It is an arithmetic number, because the mean of its divisors is an integer number (10572157714).

Almost surely, 2^21144315427 is an apocalyptic number.

21144315427 is a deficient number, since it is larger than the sum of its proper divisors (1).

21144315427 is an equidigital number, since it uses as much as digits as its factorization.

21144315427 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26880, while the sum is 34.

Adding to 21144315427 its reverse (72451344112), we get a palindrome (93595659539).

The spelling of 21144315427 in words is "twenty-one billion, one hundred forty-four million, three hundred fifteen thousand, four hundred twenty-seven".