21106212680 has 64 divisors (see below), whose sum is σ = 54285690240. Its totient is φ = 7234739712.

The previous prime is 21106212667. The next prime is 21106212689. The reversal of 21106212680 is 8621260112.

It is not an unprimeable number, because it can be changed into a prime (21106212689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2183939 + ... + 2193581.

It is an arithmetic number, because the mean of its divisors is an integer number (848213910).

Almost surely, 2^21106212680 is an apocalyptic number.

21106212680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21106212680 is an abundant number, since it is smaller than the sum of its proper divisors (33179477560).

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

21106212680 is a wasteful number, since it uses less digits than its factorization.

21106212680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17478 (or 17474 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 29.

Adding to 21106212680 its reverse (8621260112), we get a palindrome (29727472792).

The spelling of 21106212680 in words is "twenty-one billion, one hundred six million, two hundred twelve thousand, six hundred eighty".