121021020100 has 36 divisors (see below), whose sum is σ = 262718873284. Its totient is φ = 48389374080.

The previous prime is 121021020083. The next prime is 121021020149. The reversal of 121021020100 is 1020120121.

It can be written as a sum of positive squares in 6 ways, for example, as 9897464196 + 111123555904 = 99486^2 + 333352^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19054 + ... + 492346.

Almost surely, 2^121021020100 is an apocalyptic number.

121021020100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121021020100 is an abundant number, since it is smaller than the sum of its proper divisors (141697853184).

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

121021020100 is a wasteful number, since it uses less digits than its factorization.

121021020100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475864 (or 475857 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 121021020100 its reverse (1020120121), we get a palindrome (122041140221).

The spelling of 121021020100 in words is "one hundred twenty-one billion, twenty-one million, twenty thousand, one hundred".