21545330652 has 36 divisors (see below), whose sum is σ = 54787941936. Its totient is φ = 7138770240.

The previous prime is 21545330627. The next prime is 21545330689. The reversal of 21545330652 is 25603354512.

21545330652 is a `hidden beast` number, since 21 + 54 + 533 + 0 + 6 + 52 = 666.

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

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1785849 + ... + 1797872.

It is an arithmetic number, because the mean of its divisors is an integer number (1521887276).

Almost surely, 2^21545330652 is an apocalyptic number.

It is an amenable number.

21545330652 is an abundant number, since it is smaller than the sum of its proper divisors (33242611284).

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

21545330652 is a wasteful number, since it uses less digits than its factorization.

21545330652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3583898 (or 3583893 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 36.

The spelling of 21545330652 in words is "twenty-one billion, five hundred forty-five million, three hundred thirty thousand, six hundred fifty-two".