1213111320 has 32 divisors (see below), whose sum is σ = 3639334320. Its totient is φ = 323496320.

The previous prime is 1213111307. The next prime is 1213111327. The reversal of 1213111320 is 231113121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1213111320.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213111327) 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, 5054511 + ... + 5054750.

Almost surely, 2^1213111320 is an apocalyptic number.

1213111320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1213111320 is an abundant number, since it is smaller than the sum of its proper divisors (2426223000).

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

1213111320 is a wasteful number, since it uses less digits than its factorization.

1213111320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10109275 (or 10109271 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1213111320 is about 34829.7476304380. The cubic root of 1213111320 is about 1066.5147965204.

Adding to 1213111320 its reverse (231113121), we get a palindrome (1444224441).

The spelling of 1213111320 in words is "one billion, two hundred thirteen million, one hundred eleven thousand, three hundred twenty".