1213212120 has 64 divisors (see below), whose sum is σ = 3642589440. Its totient is φ = 323260800.

The previous prime is 1213212109. The next prime is 1213212137. The reversal of 1213212120 is 212123121.

It is a super-2 number, since 2×1213212120² = 2943767296229788800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1213212120.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 177975 + ... + 184665.

It is an arithmetic number, because the mean of its divisors is an integer number (56915460).

Almost surely, 2^1213212120 is an apocalyptic number.

1213212120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1213212120 is an abundant number, since it is smaller than the sum of its proper divisors (2429377320).

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

1213212120 is a wasteful number, since it uses less digits than its factorization.

1213212120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8216 (or 8212 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 1213212120 is about 34831.1946392885. The cubic root of 1213212120 is about 1066.5443353633.

Adding to 1213212120 its reverse (212123121), we get a palindrome (1425335241).

The spelling of 1213212120 in words is "one billion, two hundred thirteen million, two hundred twelve thousand, one hundred twenty".