21351205413427 has 2 divisors, whose sum is σ = 21351205413428. Its totient is φ = 21351205413426.

The previous prime is 21351205413409. The next prime is 21351205413451. The reversal of 21351205413427 is 72431450215312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21351205413427 - 2²³ = 21351197024819 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21351205413427.

It is not a weakly prime, because it can be changed into another prime (21351205413127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10675602706713 + 10675602706714.

It is an arithmetic number, because the mean of its divisors is an integer number (10675602706714).

Almost surely, 2^{21351205413427} is an apocalyptic number.

21351205413427 is a deficient number, since it is larger than the sum of its proper divisors (1).

21351205413427 is an equidigital number, since it uses as much as digits as its factorization.

21351205413427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 201600, while the sum is 40.

Adding to 21351205413427 its reverse (72431450215312), we get a palindrome (93782655628739).

The spelling of 21351205413427 in words is "twenty-one trillion, three hundred fifty-one billion, two hundred five million, four hundred thirteen thousand, four hundred twenty-seven".