21102012202120 has 32 divisors (see below), whose sum is σ = 47479816315800. Its totient is φ = 8440753527808.

The previous prime is 21102012202031. The next prime is 21102012202121. The reversal of 21102012202120 is 2120221020112.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 18488985213924 + 2613026988196 = 4299882^2 + 1616486^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21102012202094 and 21102012202103.

It is not an unprimeable number, because it can be changed into a prime (21102012202121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5433186 + ... + 8468974.

Almost surely, 2^{21102012202120} is an apocalyptic number.

21102012202120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21102012202120 is an abundant number, since it is smaller than the sum of its proper divisors (26377804113680).

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

21102012202120 is a wasteful number, since it uses less digits than its factorization.

21102012202120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3209577 (or 3209573 counting only the distinct ones).

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

Adding to 21102012202120 its reverse (2120221020112), we get a palindrome (23222233222232).

The spelling of 21102012202120 in words is "twenty-one trillion, one hundred two billion, twelve million, two hundred two thousand, one hundred twenty".