21374403431057 has 2 divisors, whose sum is σ = 21374403431058. Its totient is φ = 21374403431056.

The previous prime is 21374403431047. The next prime is 21374403431131. The reversal of 21374403431057 is 75013430447312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18836502730816 + 2537900700241 = 4340104^2 + 1593079^2 .

It is a cyclic number.

It is not a de Polignac number, because 21374403431057 - 2⁸ = 21374403430801 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21374403430999 and 21374403431017.

It is not a weakly prime, because it can be changed into another prime (21374403431047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10687201715528 + 10687201715529.

It is an arithmetic number, because the mean of its divisors is an integer number (10687201715529).

Almost surely, 2^{21374403431057} is an apocalyptic number.

It is an amenable number.

21374403431057 is a deficient number, since it is larger than the sum of its proper divisors (1).

21374403431057 is an equidigital number, since it uses as much as digits as its factorization.

21374403431057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 846720, while the sum is 44.

Adding to 21374403431057 its reverse (75013430447312), we get a palindrome (96387833878369).

The spelling of 21374403431057 in words is "twenty-one trillion, three hundred seventy-four billion, four hundred three million, four hundred thirty-one thousand, fifty-seven".