21804524646 has 16 divisors (see below), whose sum is σ = 43790002608. Its totient is φ = 7238016000.

The previous prime is 21804524641. The next prime is 21804524663. The reversal of 21804524646 is 64642540812.

It is a junction number, because it is equal to n+sod(n) for n = 21804524598 and 21804524607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21804524641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7538155 + ... + 7541046.

It is an arithmetic number, because the mean of its divisors is an integer number (2736875163).

Almost surely, 2^21804524646 is an apocalyptic number.

21804524646 is an abundant number, since it is smaller than the sum of its proper divisors (21985477962).

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

21804524646 is a wasteful number, since it uses less digits than its factorization.

21804524646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15079447.

The product of its (nonzero) digits is 368640, while the sum is 42.

The spelling of 21804524646 in words is "twenty-one billion, eight hundred four million, five hundred twenty-four thousand, six hundred forty-six".