121210100100 has 108 divisors (see below), whose sum is σ = 388009999104. Its totient is φ = 31634965440.

The previous prime is 121210100083. The next prime is 121210100159. The reversal of 121210100100 is 1001012121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1390444 + ... + 1475043.

Almost surely, 2^121210100100 is an apocalyptic number.

121210100100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121210100100 is an abundant number, since it is smaller than the sum of its proper divisors (266799899004).

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

121210100100 is a wasteful number, since it uses less digits than its factorization.

121210100100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2865554 (or 2865544 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 121210100100 its reverse (1001012121), we get a palindrome (122211112221).

The spelling of 121210100100 in words is "one hundred twenty-one billion, two hundred ten million, one hundred thousand, one hundred".