20100212001521 has 2 divisors, whose sum is σ = 20100212001522. Its totient is φ = 20100212001520.

The previous prime is 20100212001509. The next prime is 20100212001539. The reversal of 20100212001521 is 12510021200102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11955101488225 + 8145110513296 = 3457615^2 + 2853964^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20100212001521 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20100212001521.

It is not a weakly prime, because it can be changed into another prime (20100212001581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050106000760 + 10050106000761.

It is an arithmetic number, because the mean of its divisors is an integer number (10050106000761).

Almost surely, 2^{20100212001521} is an apocalyptic number.

It is an amenable number.

20100212001521 is a deficient number, since it is larger than the sum of its proper divisors (1).

20100212001521 is an equidigital number, since it uses as much as digits as its factorization.

20100212001521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80, while the sum is 17.

Adding to 20100212001521 its reverse (12510021200102), we get a palindrome (32610233201623).

The spelling of 20100212001521 in words is "twenty trillion, one hundred billion, two hundred twelve million, one thousand, five hundred twenty-one".