121210010100 has 108 divisors (see below), whose sum is σ = 381503182060. Its totient is φ = 32188492800.

The previous prime is 121210010099. The next prime is 121210010147. The reversal of 121210010100 is 1010012121.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 1911613284 + 119298396816 = 43722^2 + 345396^2 .

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

It is a congruent number.

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, 62515 + ... + 496314.

Almost surely, 2^121210010100 is an apocalyptic number.

121210010100 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 121210010100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (190751591030).

121210010100 is an abundant number, since it is smaller than the sum of its proper divisors (260293171960).

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

121210010100 is a wasteful number, since it uses less digits than its factorization.

121210010100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559090 (or 559080 counting only the distinct ones).

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

Adding to 121210010100 its reverse (1010012121), we get a palindrome (122220022221).

The spelling of 121210010100 in words is "one hundred twenty-one billion, two hundred ten million, ten thousand, one hundred".