20513221553212 has 6 divisors (see below), whose sum is σ = 35898137718128. Its totient is φ = 10256610776604.

The previous prime is 20513221553183. The next prime is 20513221553213. The reversal of 20513221553212 is 21235512231502.

It is a super-2 number, since 2×20513221553212² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20513221553213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2564152694148 + ... + 2564152694155.

Almost surely, 2^{20513221553212} is an apocalyptic number.

It is an amenable number.

20513221553212 is a deficient number, since it is larger than the sum of its proper divisors (15384916164916).

20513221553212 is a wasteful number, since it uses less digits than its factorization.

20513221553212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5128305388307 (or 5128305388305 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 34.

Adding to 20513221553212 its reverse (21235512231502), we get a palindrome (41748733784714).

The spelling of 20513221553212 in words is "twenty trillion, five hundred thirteen billion, two hundred twenty-one million, five hundred fifty-three thousand, two hundred twelve".