21152420545552 has 10 divisors (see below), whose sum is σ = 40982814807038. Its totient is φ = 10576210272768.

The previous prime is 21152420545447. The next prime is 21152420545583. The reversal of 21152420545552 is 25554502425112.

It can be written as a sum of positive squares in only one way, i.e., 18978081555456 + 2174338990096 = 4356384^2 + 1474564^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21152420545499 and 21152420545508.

It is an unprimeable number.

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, 661013142033 + ... + 661013142064.

Almost surely, 2^{21152420545552} is an apocalyptic number.

It is an amenable number.

21152420545552 is a deficient number, since it is larger than the sum of its proper divisors (19830394261486).

21152420545552 is a wasteful number, since it uses less digits than its factorization.

21152420545552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1322026284105 (or 1322026284099 counting only the distinct ones).

The product of its (nonzero) digits is 800000, while the sum is 43.

The spelling of 21152420545552 in words is "twenty-one trillion, one hundred fifty-two billion, four hundred twenty million, five hundred forty-five thousand, five hundred fifty-two".