1215120000 has 320 divisors, whose sum is σ = 4148796960. Its totient is φ = 314880000.

The previous prime is 1215119987. The next prime is 1215120007. The reversal of 1215120000 is 215121.

It is a tau number, because it is divible by the number of its divisors (320).

It is a super-2 number, since 2×1215120000² = 2953033228800000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (1215120007) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 14639959 + ... + 14640041.

Almost surely, 2^1215120000 is an apocalyptic number.

1215120000 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 1215120000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2074398480).

1215120000 is an abundant number, since it is smaller than the sum of its proper divisors (2933676960).

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

1215120000 is an frugal number, since it uses more digits than its factorization.

1215120000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181 (or 154 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 1215120000 is about 34858.5713992986. The cubic root of 1215120000 is about 1067.1031200010.

Adding to 1215120000 its reverse (215121), we get a palindrome (1215335121).

The spelling of 1215120000 in words is "one billion, two hundred fifteen million, one hundred twenty thousand".