121200000000 has 396 divisors, whose sum is σ = 407800572456. Its totient is φ = 32000000000.

The previous prime is 121199999981. The next prime is 121200000023. The reversal of 121200000000 is 2121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1199999950 + ... + 1200000050.

Almost surely, 2^121200000000 is an apocalyptic number.

121200000000 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 121200000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (203900286228).

121200000000 is an abundant number, since it is smaller than the sum of its proper divisors (286600572456).

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

121200000000 is an frugal number, since it uses more digits than its factorization.

121200000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

Adding to 121200000000 its reverse (2121), we get a palindrome (121200002121).

It can be divided in two parts, 12 and 1200000000, that multiplied together give a square (14400000000 = 120000²).

The spelling of 121200000000 in words is "one hundred twenty-one billion, two hundred million", and thus it is an aban number.