21054440406 has 32 divisors (see below), whose sum is σ = 42554323296. Its totient is φ = 6944000000.

The previous prime is 21054440401. The next prime is 21054440411. The reversal of 21054440406 is 60404445012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21054440401) and next prime (21054440411).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21054440401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 959356 + ... + 981056.

It is an arithmetic number, because the mean of its divisors is an integer number (1329822603).

Almost surely, 2^21054440406 is an apocalyptic number.

21054440406 is an abundant number, since it is smaller than the sum of its proper divisors (21499882890).

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

21054440406 is a wasteful number, since it uses less digits than its factorization.

21054440406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23408.

The product of its (nonzero) digits is 15360, while the sum is 30.

Adding to 21054440406 its reverse (60404445012), we get a palindrome (81458885418).

The spelling of 21054440406 in words is "twenty-one billion, fifty-four million, four hundred forty thousand, four hundred six".