21407629824 has 480 divisors, whose sum is σ = 74082877440. Its totient is φ = 5822668800.

The previous prime is 21407629813. The next prime is 21407629829. The reversal of 21407629824 is 42892670412.

21407629824 is a `hidden beast` number, since 2 + 14 + 0 + 7 + 629 + 8 + 2 + 4 = 666.

It is a super-2 number, since 2×21407629824² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21407629824.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21407629829) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 78994809 + ... + 78995079.

It is an arithmetic number, because the mean of its divisors is an integer number (154339328).

Almost surely, 2^21407629824 is an apocalyptic number.

21407629824 is a gapful number since it is divisible by the number (24) 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 21407629824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37041438720).

21407629824 is an abundant number, since it is smaller than the sum of its proper divisors (52675247616).

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

21407629824 is a wasteful number, since it uses less digits than its factorization.

21407629824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412 (or 393 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The spelling of 21407629824 in words is "twenty-one billion, four hundred seven million, six hundred twenty-nine thousand, eight hundred twenty-four".