1221664200106 has 16 divisors (see below), whose sum is σ = 2094733048320. Its totient is φ = 523457480880.

The previous prime is 1221664200091. The next prime is 1221664200167. The reversal of 1221664200106 is 6010024661221.

It is a happy number.

It is a super-2 number, since 2×1221664200106² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9340285 + ... + 9470176.

It is an arithmetic number, because the mean of its divisors is an integer number (130920815520).

Almost surely, 2^{1221664200106} is an apocalyptic number.

1221664200106 is a deficient number, since it is larger than the sum of its proper divisors (873068848214).

1221664200106 is a wasteful number, since it uses less digits than its factorization.

1221664200106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18815109.

The product of its (nonzero) digits is 6912, while the sum is 31.

Adding to 1221664200106 its reverse (6010024661221), we get a palindrome (7231688861327).

The spelling of 1221664200106 in words is "one trillion, two hundred twenty-one billion, six hundred sixty-four million, two hundred thousand, one hundred six".