21537425520101 has 2 divisors, whose sum is σ = 21537425520102. Its totient is φ = 21537425520100.

The previous prime is 21537425520071. The next prime is 21537425520139. The reversal of 21537425520101 is 10102552473512.

It is an a-pointer prime, because the next prime (21537425520139) can be obtained adding 21537425520101 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19149244720225 + 2388180799876 = 4375985^2 + 1545374^2 .

It is a cyclic number.

It is not a de Polignac number, because 21537425520101 - 2³⁸ = 21262547613157 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21537425520151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10768712760050 + 10768712760051.

It is an arithmetic number, because the mean of its divisors is an integer number (10768712760051).

Almost surely, 2^{21537425520101} is an apocalyptic number.

It is an amenable number.

21537425520101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21537425520101 is an equidigital number, since it uses as much as digits as its factorization.

21537425520101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84000, while the sum is 38.

Adding to 21537425520101 its reverse (10102552473512), we get a palindrome (31639977993613).

The spelling of 21537425520101 in words is "twenty-one trillion, five hundred thirty-seven billion, four hundred twenty-five million, five hundred twenty thousand, one hundred one".