121000021020 has 60 divisors (see below), whose sum is σ = 379581552504. Its totient is φ = 32266671840.

The previous prime is 121000021001. The next prime is 121000021027. The reversal of 121000021020 is 20120000121.

It is a tau number, because it is divible by the number of its divisors (60).

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 = 121000020993 and 121000021011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121000021027) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 37344066 + ... + 37347305.

Almost surely, 2^121000021020 is an apocalyptic number.

121000021020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121000021020 is an abundant number, since it is smaller than the sum of its proper divisors (258581531484).

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

121000021020 is a wasteful number, since it uses less digits than its factorization.

121000021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74691392 (or 74691381 counting only the distinct ones).

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

Adding to 121000021020 its reverse (20120000121), we get a palindrome (141120021141).

The spelling of 121000021020 in words is "one hundred twenty-one billion, twenty-one thousand, twenty".