1243211220 has 48 divisors (see below), whose sum is σ = 3867769920. Its totient is φ = 331522848.

The previous prime is 1243211219. The next prime is 1243211231. The reversal of 1243211220 is 221123421.

It is a happy number.

1243211220 is a `hidden beast` number, since 1 + 2 + 432 + 11 + 220 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1243211193 and 1243211202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1150582 + ... + 1151661.

It is an arithmetic number, because the mean of its divisors is an integer number (80578540).

Almost surely, 2^1243211220 is an apocalyptic number.

1243211220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1243211220 is an abundant number, since it is smaller than the sum of its proper divisors (2624558700).

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

1243211220 is a wasteful number, since it uses less digits than its factorization.

1243211220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2302261 (or 2302253 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1243211220 is about 35259.2005014294. The cubic root of 1243211220 is about 1075.2636728376.

Adding to 1243211220 its reverse (221123421), we get a palindrome (1464334641).

The spelling of 1243211220 in words is "one billion, two hundred forty-three million, two hundred eleven thousand, two hundred twenty".