1216302320 has 40 divisors (see below), whose sum is σ = 2840403024. Its totient is φ = 484370432.

The previous prime is 1216302319. The next prime is 1216302323. The reversal of 1216302320 is 232036121.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-3 number, since 3×1216302320³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1216302292 and 1216302301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216302323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15329 + ... + 51648.

Almost surely, 2^1216302320 is an apocalyptic number.

1216302320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1216302320 is an abundant number, since it is smaller than the sum of its proper divisors (1624100704).

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

1216302320 is a wasteful number, since it uses less digits than its factorization.

1216302320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67217 (or 67211 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 1216302320 is about 34875.5260892219. The cubic root of 1216302320 is about 1067.4491073332.

Adding to 1216302320 its reverse (232036121), we get a palindrome (1448338441).

The spelling of 1216302320 in words is "one billion, two hundred sixteen million, three hundred two thousand, three hundred twenty".