21429211776 has 256 divisors, whose sum is σ = 67504742400. Its totient is φ = 5894000640.

The previous prime is 21429211747. The next prime is 21429211787. The reversal of 21429211776 is 67711292412.

It is a super-2 number, since 2×21429211776² (a number of 21 digits) contains 22 as substring.

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

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 31 ways as a sum of consecutive naturals, for example, 19081551 + ... + 19082673.

It is an arithmetic number, because the mean of its divisors is an integer number (263690400).

Almost surely, 2^21429211776 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 21429211776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33752371200).

21429211776 is an abundant number, since it is smaller than the sum of its proper divisors (46075530624).

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

21429211776 is a wasteful number, since it uses less digits than its factorization.

21429211776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1407 (or 1395 counting only the distinct ones).

The product of its digits is 84672, while the sum is 42.

The spelling of 21429211776 in words is "twenty-one billion, four hundred twenty-nine million, two hundred eleven thousand, seven hundred seventy-six".