21325609044 has 336 divisors, whose sum is σ = 61682974080. Its totient is φ = 6424531200.

The previous prime is 21325609037. The next prime is 21325609051. The reversal of 21325609044 is 44090652312.

It is a happy number.

21325609044 is a `hidden beast` number, since 2 + 1 + 3 + 2 + 5 + 609 + 0 + 44 = 666.

It is an interprime number because it is at equal distance from previous prime (21325609037) and next prime (21325609051).

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 (19) of ones.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 207044697 + ... + 207044799.

It is an arithmetic number, because the mean of its divisors is an integer number (183580280).

Almost surely, 2^21325609044 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21325609044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30841487040).

21325609044 is an abundant number, since it is smaller than the sum of its proper divisors (40357365036).

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

21325609044 is a wasteful number, since it uses less digits than its factorization.

21325609044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282 (or 265 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 21325609044 in words is "twenty-one billion, three hundred twenty-five million, six hundred nine thousand, forty-four".