1521391218 has 48 divisors (see below), whose sum is σ = 3228657120. Its totient is φ = 476606592.

The previous prime is 1521391159. The next prime is 1521391219. The reversal of 1521391218 is 8121931251.

It is not an unprimeable number, because it can be changed into a prime (1521391219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4514346 + ... + 4514682.

It is an arithmetic number, because the mean of its divisors is an integer number (67263690).

Almost surely, 2^1521391218 is an apocalyptic number.

1521391218 is an abundant number, since it is smaller than the sum of its proper divisors (1707265902).

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

1521391218 is a wasteful number, since it uses less digits than its factorization.

1521391218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 759 (or 560 counting only the distinct ones).

The product of its digits is 4320, while the sum is 33.

The square root of 1521391218 is about 39005.0152929082. The cubic root of 1521391218 is about 1150.1300969391.

The spelling of 1521391218 in words is "one billion, five hundred twenty-one million, three hundred ninety-one thousand, two hundred eighteen".