21646635052 has 24 divisors (see below), whose sum is σ = 43296664320. Its totient is φ = 9276402000.

The previous prime is 21646635047. The next prime is 21646635061. The reversal of 21646635052 is 25053664612.

It is a happy number.

It is a super-3 number, since 3×21646635052³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21646634996 and 21646635014.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 489849 + ... + 532207.

It is an arithmetic number, because the mean of its divisors is an integer number (1804027680).

Almost surely, 2^21646635052 is an apocalyptic number.

It is an amenable number.

21646635052 is an abundant number, since it is smaller than the sum of its proper divisors (21650029268).

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

21646635052 is a wasteful number, since it uses less digits than its factorization.

21646635052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60621 (or 60619 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 40.

The spelling of 21646635052 in words is "twenty-one billion, six hundred forty-six million, six hundred thirty-five thousand, fifty-two".