21121101021020 has 144 divisors (see below), whose sum is σ = 60616083332448. Its totient is φ = 6076800253440.

The previous prime is 21121101020983. The next prime is 21121101021043. The reversal of 21121101021020 is 2012010112112.

It is a super-2 number, since 2×21121101021020² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 21121101020986 and 21121101021004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 75217007 + ... + 75497286.

It is an arithmetic number, because the mean of its divisors is an integer number (420945023142).

Almost surely, 2^{21121101021020} is an apocalyptic number.

21121101021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121101021020 is an abundant number, since it is smaller than the sum of its proper divisors (39494982311428).

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

21121101021020 is a wasteful number, since it uses less digits than its factorization.

21121101021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150714340 (or 150714331 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21121101021020 its reverse (2012010112112), we get a palindrome (23133111133132).

The spelling of 21121101021020 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred one million, twenty-one thousand, twenty".