21140420201 has 2 divisors, whose sum is σ = 21140420202. Its totient is φ = 21140420200.

The previous prime is 21140420173. The next prime is 21140420219. The reversal of 21140420201 is 10202404112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16078240000 + 5062180201 = 126800^2 + 71149^2 .

It is a cyclic number.

It is not a de Polignac number, because 21140420201 - 2²² = 21136225897 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21140420201.

It is not a weakly prime, because it can be changed into another prime (21140420251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10570210100 + 10570210101.

It is an arithmetic number, because the mean of its divisors is an integer number (10570210101).

Almost surely, 2^21140420201 is an apocalyptic number.

It is an amenable number.

21140420201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21140420201 is an equidigital number, since it uses as much as digits as its factorization.

21140420201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21140420201 its reverse (10202404112), we get a palindrome (31342824313).

The spelling of 21140420201 in words is "twenty-one billion, one hundred forty million, four hundred twenty thousand, two hundred one".