20415521231101 has 2 divisors, whose sum is σ = 20415521231102. Its totient is φ = 20415521231100.

The previous prime is 20415521231087. The next prime is 20415521231153. The reversal of 20415521231101 is 10113212551402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14228934559876 + 6186586671225 = 3772126^2 + 2487285^2 .

It is a cyclic number.

It is not a de Polignac number, because 20415521231101 - 2¹⁵ = 20415521198333 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20415521231101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20415521291101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10207760615550 + 10207760615551.

It is an arithmetic number, because the mean of its divisors is an integer number (10207760615551).

Almost surely, 2^{20415521231101} is an apocalyptic number.

It is an amenable number.

20415521231101 is a deficient number, since it is larger than the sum of its proper divisors (1).

20415521231101 is an equidigital number, since it uses as much as digits as its factorization.

20415521231101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2400, while the sum is 28.

Adding to 20415521231101 its reverse (10113212551402), we get a palindrome (30528733782503).

The spelling of 20415521231101 in words is "twenty trillion, four hundred fifteen billion, five hundred twenty-one million, two hundred thirty-one thousand, one hundred one".