21201210212020 has 12 divisors (see below), whose sum is σ = 44522541445284. Its totient is φ = 8480484084800.

The previous prime is 21201210211999. The next prime is 21201210212057. The reversal of 21201210212020 is 2021201210212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 14897917087524 + 6303293124496 = 3859782^2 + 2510636^2 .

It is a super-2 number, since 2×21201210212020² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21201210211985 and 21201210212003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 530030255281 + ... + 530030255320.

It is an arithmetic number, because the mean of its divisors is an integer number (3710211787107).

Almost surely, 2^{21201210212020} is an apocalyptic number.

21201210212020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201210212020 is an abundant number, since it is smaller than the sum of its proper divisors (23321331233264).

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

21201210212020 is a wasteful number, since it uses less digits than its factorization.

21201210212020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060060510610 (or 1060060510608 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21201210212020 its reverse (2021201210212), we get a palindrome (23222411422232).

The spelling of 21201210212020 in words is "twenty-one trillion, two hundred one billion, two hundred ten million, two hundred twelve thousand, twenty".