121121010100 has 36 divisors (see below), whose sum is σ = 278293336524. Its totient is φ = 45598497280.

The previous prime is 121121010077. The next prime is 121121010103. The reversal of 121121010100 is 1010121121.

It can be written as a sum of positive squares in 6 ways, for example, as 1042127524 + 120078882576 = 32282^2 + 346524^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121121010103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35622127 + ... + 35625526.

It is an arithmetic number, because the mean of its divisors is an integer number (7730370459).

Almost surely, 2^121121010100 is an apocalyptic number.

121121010100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121121010100 is an abundant number, since it is smaller than the sum of its proper divisors (157172326424).

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

121121010100 is a wasteful number, since it uses less digits than its factorization.

121121010100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71247684 (or 71247677 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 121121010100 its reverse (1010121121), we get a palindrome (122131131221).

The spelling of 121121010100 in words is "one hundred twenty-one billion, one hundred twenty-one million, ten thousand, one hundred".