121211012100 has 144 divisors (see below), whose sum is σ = 362178305216. Its totient is φ = 31275072000.

The previous prime is 121211012053. The next prime is 121211012147. The reversal of 121211012100 is 1210112121.

It is an interprime number because it is at equal distance from previous prime (121211012053) and next prime (121211012147).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1978935 + ... + 2039265.

Almost surely, 2^121211012100 is an apocalyptic number.

121211012100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121211012100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (181089152608).

121211012100 is an abundant number, since it is smaller than the sum of its proper divisors (240967293116).

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

121211012100 is a wasteful number, since it uses less digits than its factorization.

121211012100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60566 (or 60559 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 121211012100 its reverse (1210112121), we get a palindrome (122421124221).

The spelling of 121211012100 in words is "one hundred twenty-one billion, two hundred eleven million, twelve thousand, one hundred".