21020031312220 has 48 divisors (see below), whose sum is σ = 44176552701120. Its totient is φ = 8401444844544.

The previous prime is 21020031312197. The next prime is 21020031312257. The reversal of 21020031312220 is 2221313002012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 314651862 + ... + 314718658.

It is an arithmetic number, because the mean of its divisors is an integer number (920344847940).

Almost surely, 2^{21020031312220} is an apocalyptic number.

21020031312220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21020031312220 is an abundant number, since it is smaller than the sum of its proper divisors (23156521388900).

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

21020031312220 is a wasteful number, since it uses less digits than its factorization.

21020031312220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78862 (or 78860 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21020031312220 its reverse (2221313002012), we get a palindrome (23241344314232).

The spelling of 21020031312220 in words is "twenty-one trillion, twenty billion, thirty-one million, three hundred twelve thousand, two hundred twenty".