121021220100 has 288 divisors, whose sum is σ = 425747750400. Its totient is φ = 26159155200.

The previous prime is 121021220059. The next prime is 121021220101. The reversal of 121021220100 is 1022120121.

It is a super-2 number, since 2×121021220100² (a number of 23 digits) contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (121021220101) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1009131 + ... + 1122669.

It is an arithmetic number, because the mean of its divisors is an integer number (1478290800).

Almost surely, 2^121021220100 is an apocalyptic number.

121021220100 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 121021220100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212873875200).

121021220100 is an abundant number, since it is smaller than the sum of its proper divisors (304726530300).

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

121021220100 is a wasteful number, since it uses less digits than its factorization.

121021220100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113603 (or 113596 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 121021220100 its reverse (1022120121), we get a palindrome (122043340221).

The spelling of 121021220100 in words is "one hundred twenty-one billion, twenty-one million, two hundred twenty thousand, one hundred".