121210100 has 72 divisors (see below), whose sum is σ = 290043936. Its totient is φ = 43600000.

The previous prime is 121210081. The next prime is 121210157. The reversal of 121210100 is 1012121.

It is a congruent number.

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, 110555 + ... + 111645.

It is an arithmetic number, because the mean of its divisors is an integer number (4028388).

Almost surely, 2^121210100 is an apocalyptic number.

121210100 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 121210100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145021968).

121210100 is an abundant number, since it is smaller than the sum of its proper divisors (168833836).

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

121210100 is a wasteful number, since it uses less digits than its factorization.

121210100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1217 (or 1210 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 121210100 is about 11009.5458580270. The cubic root of 121210100 is about 494.8948523388.

Adding to 121210100 its reverse (1012121), we get a palindrome (122222221).

The spelling of 121210100 in words is "one hundred twenty-one million, two hundred ten thousand, one hundred".