1215720360 has 256 divisors, whose sum is σ = 4203705600. Its totient is φ = 312339456.

The previous prime is 1215720349. The next prime is 1215720379. The reversal of 1215720360 is 630275121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3834922 + ... + 3835238.

It is an arithmetic number, because the mean of its divisors is an integer number (16420725).

Almost surely, 2^1215720360 is an apocalyptic number.

1215720360 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1215720360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2101852800).

1215720360 is an abundant number, since it is smaller than the sum of its proper divisors (2987985240).

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

1215720360 is a wasteful number, since it uses less digits than its factorization.

1215720360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457 (or 447 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 1215720360 is about 34867.1817042904. The cubic root of 1215720360 is about 1067.2788339357.

Adding to 1215720360 its reverse (630275121), we get a palindrome (1845995481).

The spelling of 1215720360 in words is "one billion, two hundred fifteen million, seven hundred twenty thousand, three hundred sixty".