21122430444 has 72 divisors (see below), whose sum is σ = 55630568448. Its totient is φ = 6749969760.

The previous prime is 21122430383. The next prime is 21122430451. The reversal of 21122430444 is 44403422112.

21122430444 is a `hidden beast` number, since 211 + 2 + 2 + 4 + 3 + 0 + 444 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30969 + ... + 207855.

It is an arithmetic number, because the mean of its divisors is an integer number (772646784).

Almost surely, 2^21122430444 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 21122430444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27815284224).

21122430444 is an abundant number, since it is smaller than the sum of its proper divisors (34508138004).

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

21122430444 is a wasteful number, since it uses less digits than its factorization.

21122430444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177035 (or 177030 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 27.

Adding to 21122430444 its reverse (44403422112), we get a palindrome (65525852556).

The spelling of 21122430444 in words is "twenty-one billion, one hundred twenty-two million, four hundred thirty thousand, four hundred forty-four".