400021200021320 has 128 divisors (see below), whose sum is σ = 938205146511360. Its totient is φ = 153354529152000.

The previous prime is 400021200021281. The next prime is 400021200021349. The reversal of 400021200021320 is 23120002120004.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3421060697 + ... + 3421177623.

It is an arithmetic number, because the mean of its divisors is an integer number (7329727707120).

Almost surely, 2^{400021200021320} is an apocalyptic number.

400021200021320 is a gapful number since it is divisible by the number (40) 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 400021200021320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (469102573255680).

400021200021320 is an abundant number, since it is smaller than the sum of its proper divisors (538183946490040).

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

400021200021320 is a wasteful number, since it uses less digits than its factorization.

400021200021320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151543 (or 151539 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 400021200021320 its reverse (23120002120004), we get a palindrome (423141202141324).

The spelling of 400021200021320 in words is "four hundred trillion, twenty-one billion, two hundred million, twenty-one thousand, three hundred twenty".