21221112001020 has 96 divisors (see below), whose sum is σ = 59613816278016. Its totient is φ = 5640422323200.

The previous prime is 21221112001007. The next prime is 21221112001057. The reversal of 21221112001020 is 2010021112212.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

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, 491128257 + ... + 491171463.

It is an arithmetic number, because the mean of its divisors is an integer number (620977252896).

Almost surely, 2^{21221112001020} is an apocalyptic number.

21221112001020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221112001020 is an abundant number, since it is smaller than the sum of its proper divisors (38392704276996).

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

21221112001020 is a wasteful number, since it uses less digits than its factorization.

21221112001020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69851 (or 69849 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21221112001020 its reverse (2010021112212), we get a palindrome (23231133113232).

The spelling of 21221112001020 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twelve million, one thousand, twenty".