1215120666 has 32 divisors (see below), whose sum is σ = 2455574400. Its totient is φ = 400840704.

The previous prime is 1215120653. The next prime is 1215120667. The reversal of 1215120666 is 6660215121.

It is not an unprimeable number, because it can be changed into a prime (1215120667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 227806 + ... + 233078.

It is an arithmetic number, because the mean of its divisors is an integer number (76736700).

Almost surely, 2^1215120666 is an apocalyptic number.

1215120666 is an abundant number, since it is smaller than the sum of its proper divisors (1240453734).

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

1215120666 is a wasteful number, since it uses less digits than its factorization.

1215120666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5670.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 1215120666 is about 34858.5809521845. The cubic root of 1215120666 is about 1067.1033149585.

Adding to 1215120666 its reverse (6660215121), we get a palindrome (7875335787).

The spelling of 1215120666 in words is "one billion, two hundred fifteen million, one hundred twenty thousand, six hundred sixty-six".