1243321420 has 24 divisors (see below), whose sum is σ = 2848336848. Its totient is φ = 452116800.

The previous prime is 1243321381. The next prime is 1243321423. The reversal of 1243321420 is 241233421.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 1243321391 and 1243321400.

It is not an unprimeable number, because it can be changed into a prime (1243321423) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2825511 + ... + 2825950.

It is an arithmetic number, because the mean of its divisors is an integer number (118680702).

Almost surely, 2^1243321420 is an apocalyptic number.

1243321420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1243321420 is an abundant number, since it is smaller than the sum of its proper divisors (1605015428).

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

1243321420 is a wasteful number, since it uses less digits than its factorization.

1243321420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5651481 (or 5651479 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 1243321420 is about 35260.7631794889. The cubic root of 1243321420 is about 1075.2954428629.

Adding to 1243321420 its reverse (241233421), we get a palindrome (1484554841).

The spelling of 1243321420 in words is "one billion, two hundred forty-three million, three hundred twenty-one thousand, four hundred twenty".