1211242320 has 60 divisors (see below), whose sum is σ = 4067757876. Its totient is φ = 322997760.

The previous prime is 1211242313. The next prime is 1211242327. The reversal of 1211242320 is 232421121.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1211242313) and next prime (1211242327).

It can be written as a sum of positive squares in 2 ways, for example, as 181602576 + 1029639744 = 13476^2 + 32088^2 .

It is a tau number, because it is divible by the number of its divisors (60).

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 = 1211242293 and 1211242302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211242327) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 840421 + ... + 841860.

Almost surely, 2^1211242320 is an apocalyptic number.

1211242320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211242320 is an abundant number, since it is smaller than the sum of its proper divisors (2856515556).

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

1211242320 is a wasteful number, since it uses less digits than its factorization.

1211242320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1682300 (or 1682291 counting only the distinct ones).

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

The square root of 1211242320 is about 34802.9067751531. The cubic root of 1211242320 is about 1065.9668004496.

Adding to 1211242320 its reverse (232421121), we get a palindrome (1443663441).

The spelling of 1211242320 in words is "one billion, two hundred eleven million, two hundred forty-two thousand, three hundred twenty".