21141905568 has 384 divisors, whose sum is σ = 71153510400. Its totient is φ = 5350883328.

The previous prime is 21141905567. The next prime is 21141905573. The reversal of 21141905568 is 86550914112.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (21141905567) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 55783203 + ... + 55783581.

It is an arithmetic number, because the mean of its divisors is an integer number (185295600).

Almost surely, 2^21141905568 is an apocalyptic number.

21141905568 is a gapful number since it is divisible by the number (28) 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 21141905568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35576755200).

21141905568 is an abundant number, since it is smaller than the sum of its proper divisors (50011604832).

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

21141905568 is a wasteful number, since it uses less digits than its factorization.

21141905568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692 (or 684 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 42.

The spelling of 21141905568 in words is "twenty-one billion, one hundred forty-one million, nine hundred five thousand, five hundred sixty-eight".