21047551122 has 64 divisors (see below), whose sum is σ = 47455027200. Its totient is φ = 6178939200.

The previous prime is 21047551087. The next prime is 21047551141. The reversal of 21047551122 is 22115574012.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21047551122.

It is an unprimeable number.

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, 110379 + ... + 232977.

It is an arithmetic number, because the mean of its divisors is an integer number (741484800).

Almost surely, 2^21047551122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21047551122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23727513600).

21047551122 is an abundant number, since it is smaller than the sum of its proper divisors (26407476078).

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

21047551122 is a wasteful number, since it uses less digits than its factorization.

21047551122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122719.

The product of its (nonzero) digits is 5600, while the sum is 30.

The spelling of 21047551122 in words is "twenty-one billion, forty-seven million, five hundred fifty-one thousand, one hundred twenty-two".