21546952998021 has 48 divisors (see below), whose sum is σ = 36992287423680. Its totient is φ = 12290597026560.

The previous prime is 21546952998019. The next prime is 21546952998091. The reversal of 21546952998021 is 12089925964512.

21546952998021 is a `hidden beast` number, since 2 + 1 + 5 + 4 + 6 + 9 + 529 + 9 + 80 + 21 = 666.

It is not a de Polignac number, because 21546952998021 - 2¹ = 21546952998019 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21546952998021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21546952998091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 125430886 + ... + 125602551.

It is an arithmetic number, because the mean of its divisors is an integer number (770672654660).

Almost surely, 2^{21546952998021} is an apocalyptic number.

It is an amenable number.

21546952998021 is a deficient number, since it is larger than the sum of its proper divisors (15445334425659).

21546952998021 is a wasteful number, since it uses less digits than its factorization.

21546952998021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251033491 (or 251033468 counting only the distinct ones).

The product of its (nonzero) digits is 27993600, while the sum is 63.

The spelling of 21546952998021 in words is "twenty-one trillion, five hundred forty-six billion, nine hundred fifty-two million, nine hundred ninety-eight thousand, twenty-one".