1216231612 has 24 divisors (see below), whose sum is σ = 2260845216. Its totient is φ = 570505728.

The previous prime is 1216231589. The next prime is 1216231613. The reversal of 1216231612 is 2161326121.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216231613) 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, 7288 + ... + 49855.

It is an arithmetic number, because the mean of its divisors is an integer number (94201884).

Almost surely, 2^1216231612 is an apocalyptic number.

It is an amenable number.

1216231612 is a deficient number, since it is larger than the sum of its proper divisors (1044613604).

1216231612 is a wasteful number, since it uses less digits than its factorization.

1216231612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57477 (or 57475 counting only the distinct ones).

The product of its digits is 864, while the sum is 25.

The square root of 1216231612 is about 34874.5123550137. The cubic root of 1216231612 is about 1067.4284220554.

Adding to 1216231612 its reverse (2161326121), we get a palindrome (3377557733).

The spelling of 1216231612 in words is "one billion, two hundred sixteen million, two hundred thirty-one thousand, six hundred twelve".