1212506400 has 144 divisors (see below), whose sum is σ = 4510586304. Its totient is φ = 277140480.

The previous prime is 1212506377. The next prime is 1212506401. The reversal of 1212506400 is 46052121.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (1212506401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19287 + ... + 52886.

It is an arithmetic number, because the mean of its divisors is an integer number (31323516).

Almost surely, 2^1212506400 is an apocalyptic number.

1212506400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1212506400 is an abundant number, since it is smaller than the sum of its proper divisors (3298079904).

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

1212506400 is a wasteful number, since it uses less digits than its factorization.

1212506400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72203 (or 72190 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 1212506400 is about 34821.0625914833. The cubic root of 1212506400 is about 1066.3374939140.

Adding to 1212506400 its reverse (46052121), we get a palindrome (1258558521).

The spelling of 1212506400 in words is "one billion, two hundred twelve million, five hundred six thousand, four hundred".