21220100012 has 48 divisors (see below), whose sum is σ = 39496138752. Its totient is φ = 9954204480.

The previous prime is 21220099991. The next prime is 21220100021. The reversal of 21220100012 is 21000102212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21220099966 and 21220100002.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2054453 + ... + 2064755.

It is an arithmetic number, because the mean of its divisors is an integer number (822836224).

Almost surely, 2^21220100012 is an apocalyptic number.

It is an amenable number.

21220100012 is a deficient number, since it is larger than the sum of its proper divisors (18276038740).

21220100012 is a wasteful number, since it uses less digits than its factorization.

21220100012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10758 (or 10756 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21220100012 its reverse (21000102212), we get a palindrome (42220202224).

The spelling of 21220100012 in words is "twenty-one billion, two hundred twenty million, one hundred thousand, twelve".