121210000020 has 96 divisors (see below), whose sum is σ = 383489366400. Its totient is φ = 31774816512.

The previous prime is 121209999991. The next prime is 121210000033. The reversal of 121210000020 is 20000012121.

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

It is a junction number, because it is equal to n+sod(n) for n = 121209999957 and 121210000011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1870369 + ... + 1934088.

It is an arithmetic number, because the mean of its divisors is an integer number (3994680900).

Almost surely, 2^121210000020 is an apocalyptic number.

121210000020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121210000020 is an abundant number, since it is smaller than the sum of its proper divisors (262279366380).

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

121210000020 is a wasteful number, since it uses less digits than its factorization.

121210000020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3804534 (or 3804526 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 121210000020 its reverse (20000012121), we get a palindrome (141210012141).

The spelling of 121210000020 in words is "one hundred twenty-one billion, two hundred ten million, twenty", and thus it is an aban number.