21345621120 has 512 divisors, whose sum is σ = 77905152000. Its totient is φ = 5521747968.

The previous prime is 21345621119. The next prime is 21345621131. The reversal of 21345621120 is 2112654312.

21345621120 is a `hidden beast` number, since 2 + 1 + 34 + 5 + 621 + 1 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 119249191 + ... + 119249369.

It is an arithmetic number, because the mean of its divisors is an integer number (152158500).

Almost surely, 2^21345621120 is an apocalyptic number.

21345621120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21345621120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38952576000).

21345621120 is an abundant number, since it is smaller than the sum of its proper divisors (56559530880).

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

21345621120 is a wasteful number, since it uses less digits than its factorization.

21345621120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377 (or 359 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The spelling of 21345621120 in words is "twenty-one billion, three hundred forty-five million, six hundred twenty-one thousand, one hundred twenty".