1215860980 has 24 divisors (see below), whose sum is σ = 2557499112. Its totient is φ = 485546112.

The previous prime is 1215860963. The next prime is 1215860981. The reversal of 1215860980 is 890685121.

It can be written as a sum of positive squares in 4 ways, for example, as 83942244 + 1131918736 = 9162^2 + 33644^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215860981) 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, 37327 + ... + 61846.

It is an arithmetic number, because the mean of its divisors is an integer number (106562463).

Almost surely, 2^1215860980 is an apocalyptic number.

1215860980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1215860980 is an abundant number, since it is smaller than the sum of its proper divisors (1341638132).

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

1215860980 is a wasteful number, since it uses less digits than its factorization.

1215860980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99795 (or 99793 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 40.

The square root of 1215860980 is about 34869.1981553921. The cubic root of 1215860980 is about 1067.3199823687.

The spelling of 1215860980 in words is "one billion, two hundred fifteen million, eight hundred sixty thousand, nine hundred eighty".