21048821934 has 128 divisors (see below), whose sum is σ = 50486768640. Its totient is φ = 5723633664.

The previous prime is 21048821929. The next prime is 21048821947. The reversal of 21048821934 is 43912884012.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 48611382 + ... + 48611814.

It is an arithmetic number, because the mean of its divisors is an integer number (394427880).

Almost surely, 2^21048821934 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21048821934, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25243384320).

21048821934 is an abundant number, since it is smaller than the sum of its proper divisors (29437946706).

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

21048821934 is a wasteful number, since it uses less digits than its factorization.

21048821934 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 954.

The product of its (nonzero) digits is 110592, while the sum is 42.

The spelling of 21048821934 in words is "twenty-one billion, forty-eight million, eight hundred twenty-one thousand, nine hundred thirty-four".