1215013220 has 24 divisors (see below), whose sum is σ = 2552311608. Its totient is φ = 485856000.

The previous prime is 1215013211. The next prime is 1215013223. The reversal of 1215013220 is 223105121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 63904036 + 1151109184 = 7994^2 + 33928^2 .

It is not an unprimeable number, because it can be changed into a prime (1215013223) 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 7 ways as a sum of consecutive naturals, for example, 76790 + ... + 91250.

It is an arithmetic number, because the mean of its divisors is an integer number (106346317).

Almost surely, 2^1215013220 is an apocalyptic number.

1215013220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1215013220 is an abundant number, since it is smaller than the sum of its proper divisors (1337298388).

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

1215013220 is a wasteful number, since it uses less digits than its factorization.

1215013220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18671 (or 18669 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 1215013220 is about 34857.0397480911. The cubic root of 1215013220 is about 1067.0718614671.

Adding to 1215013220 its reverse (223105121), we get a palindrome (1438118341).

The spelling of 1215013220 in words is "one billion, two hundred fifteen million, thirteen thousand, two hundred twenty".