1212211220100 has 72 divisors (see below), whose sum is σ = 3628273608960. Its totient is φ = 312109553280.

The previous prime is 1212211220083. The next prime is 1212211220117. The reversal of 1212211220100 is 10221122121.

It is an interprime number because it is at equal distance from previous prime (1212211220083) and next prime (1212211220117).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1212211220100.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 69658612 + ... + 69676011.

Almost surely, 2^{1212211220100} is an apocalyptic number.

1212211220100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1212211220100 is an abundant number, since it is smaller than the sum of its proper divisors (2416062388860).

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

1212211220100 is a wasteful number, since it uses less digits than its factorization.

1212211220100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139334669 (or 139334662 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1212211220100 its reverse (10221122121), we get a palindrome (1222432342221).

The spelling of 1212211220100 in words is "one trillion, two hundred twelve billion, two hundred eleven million, two hundred twenty thousand, one hundred".