1215221672 has 32 divisors (see below), whose sum is σ = 2605742400. Its totient is φ = 520470144.

The previous prime is 1215221671. The next prime is 1215221699. The reversal of 1215221672 is 2761225121.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1215221671) 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, 91979 + ... + 104357.

It is an arithmetic number, because the mean of its divisors is an integer number (81429450).

Almost surely, 2^1215221672 is an apocalyptic number.

It is an amenable number.

1215221672 is an abundant number, since it is smaller than the sum of its proper divisors (1390520728).

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

1215221672 is a wasteful number, since it uses less digits than its factorization.

1215221672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14145 (or 14141 counting only the distinct ones).

The product of its digits is 3360, while the sum is 29.

The square root of 1215221672 is about 34860.0297188628. The cubic root of 1215221672 is about 1067.1328815286.

Adding to 1215221672 its reverse (2761225121), we get a palindrome (3976446793).

The spelling of 1215221672 in words is "one billion, two hundred fifteen million, two hundred twenty-one thousand, six hundred seventy-two".