20281518252 has 36 divisors (see below), whose sum is σ = 51271854816. Its totient is φ = 6759888480.

The previous prime is 20281518199. The next prime is 20281518259. The reversal of 20281518252 is 25281518202.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×20281518252² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20281518259) 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 in 11 ways as a sum of consecutive naturals, for example, 550638 + ... + 586314.

Almost surely, 2^20281518252 is an apocalyptic number.

It is an amenable number.

20281518252 is an abundant number, since it is smaller than the sum of its proper divisors (30990336564).

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

20281518252 is a wasteful number, since it uses less digits than its factorization.

20281518252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51478 (or 51473 counting only the distinct ones).

The product of its (nonzero) digits is 25600, while the sum is 36.

The spelling of 20281518252 in words is "twenty billion, two hundred eighty-one million, five hundred eighteen thousand, two hundred fifty-two".