21210132121020 has 36 divisors (see below), whose sum is σ = 64337400767640. Its totient is φ = 5656035232224.

The previous prime is 21210132121019. The next prime is 21210132121049. The reversal of 21210132121020 is 2012123101212.

21210132121020 is a `hidden beast` number, since 2 + 12 + 101 + 321 + 210 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×21210132121020² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21210132120984 and 21210132121002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58917033490 + ... + 58917033849.

Almost surely, 2^{21210132121020} is an apocalyptic number.

21210132121020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210132121020 is an abundant number, since it is smaller than the sum of its proper divisors (43127268646620).

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

21210132121020 is a wasteful number, since it uses less digits than its factorization.

21210132121020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117834067354 (or 117834067349 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 21210132121020 its reverse (2012123101212), we get a palindrome (23222255222232).

The spelling of 21210132121020 in words is "twenty-one trillion, two hundred ten billion, one hundred thirty-two million, one hundred twenty-one thousand, twenty".