20515551121452 has 12 divisors (see below), whose sum is σ = 47869619283416. Its totient is φ = 6838517040480.

The previous prime is 20515551121423. The next prime is 20515551121523. The reversal of 20515551121452 is 25412115551502.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 20515551121452.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 854814630049 + ... + 854814630072.

Almost surely, 2^{20515551121452} is an apocalyptic number.

It is an amenable number.

20515551121452 is an abundant number, since it is smaller than the sum of its proper divisors (27354068161964).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20515551121452 is a wasteful number, since it uses less digits than its factorization.

20515551121452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1709629260128 (or 1709629260126 counting only the distinct ones).

The product of its (nonzero) digits is 100000, while the sum is 39.

Adding to 20515551121452 its reverse (25412115551502), we get a palindrome (45927666672954).

The spelling of 20515551121452 in words is "twenty trillion, five hundred fifteen billion, five hundred fifty-one million, one hundred twenty-one thousand, four hundred fifty-two".