21029400576 has 416 divisors, whose sum is σ = 66052224000. Its totient is φ = 6601900032.

The previous prime is 21029400541. The next prime is 21029400577. The reversal of 21029400576 is 67500492012.

21029400576 is a `hidden beast` number, since 21 + 0 + 29 + 40 + 0 + 576 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21029400576.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21029400577) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 253366231 + ... + 253366313.

Almost surely, 2^21029400576 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 21029400576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33026112000).

21029400576 is an abundant number, since it is smaller than the sum of its proper divisors (45022823424).

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

21029400576 is an equidigital number, since it uses as much as digits as its factorization.

21029400576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224 (or 196 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

Adding to 21029400576 its reverse (67500492012), we get a palindrome (88529892588).

The spelling of 21029400576 in words is "twenty-one billion, twenty-nine million, four hundred thousand, five hundred seventy-six".