21020043792 has 80 divisors (see below), whose sum is σ = 59545528128. Its totient is φ = 6336675840.

The previous prime is 21020043787. The next prime is 21020043797. The reversal of 21020043792 is 29734002012.

It is an interprime number because it is at equal distance from previous prime (21020043787) and next prime (21020043797).

It is not an unprimeable number, because it can be changed into a prime (21020043797) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1233 + ... + 205040.

Almost surely, 2^21020043792 is an apocalyptic number.

21020043792 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21020043792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29772764064).

21020043792 is an abundant number, since it is smaller than the sum of its proper divisors (38525484336).

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

21020043792 is a wasteful number, since it uses less digits than its factorization.

21020043792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206488 (or 206482 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

It can be divided in two parts, 210 and 20043792, that added together give a palindrome (20044002).

The spelling of 21020043792 in words is "twenty-one billion, twenty million, forty-three thousand, seven hundred ninety-two".