21434542752 has 216 divisors, whose sum is σ = 69532906464. Its totient is φ = 5763545088.

The previous prime is 21434542739. The next prime is 21434542781. The reversal of 21434542752 is 25724543412.

It is a self number, because there is not a number n which added to its sum of digits gives 21434542752.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1351573 + ... + 1367339.

It is an arithmetic number, because the mean of its divisors is an integer number (321911604).

Almost surely, 2^21434542752 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 21434542752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34766453232).

21434542752 is an abundant number, since it is smaller than the sum of its proper divisors (48098363712).

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

21434542752 is a wasteful number, since it uses less digits than its factorization.

21434542752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15828 (or 15796 counting only the distinct ones).

The product of its digits is 268800, while the sum is 39.

The spelling of 21434542752 in words is "twenty-one billion, four hundred thirty-four million, five hundred forty-two thousand, seven hundred fifty-two".