21287243232160 has 48 divisors (see below), whose sum is σ = 51240001064616. Its totient is φ = 8354238850048.

The previous prime is 21287243232139. The next prime is 21287243232169. The reversal of 21287243232160 is 6123234278212.

It can be written as a sum of positive squares in 4 ways, for example, as 18674739959184 + 2612503272976 = 4321428^2 + 1616324^2 .

It is not an unprimeable number, because it can be changed into a prime (21287243232169) 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 7 ways as a sum of consecutive naturals, for example, 1255135579 + ... + 1255152538.

Almost surely, 2^{21287243232160} is an apocalyptic number.

21287243232160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21287243232160 is an abundant number, since it is smaller than the sum of its proper divisors (29952757832456).

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

21287243232160 is a wasteful number, since it uses less digits than its factorization.

21287243232160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2510288185 (or 2510288177 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 43.

The spelling of 21287243232160 in words is "twenty-one trillion, two hundred eighty-seven billion, two hundred forty-three million, two hundred thirty-two thousand, one hundred sixty".