1516721320 has 16 divisors (see below), whose sum is σ = 3412623060. Its totient is φ = 606688512.

The previous prime is 1516721287. The next prime is 1516721363. The reversal of 1516721320 is 231276151.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1409101444 + 107619876 = 37538^2 + 10374^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18958977 + ... + 18959056.

Almost surely, 2^1516721320 is an apocalyptic number.

1516721320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1516721320 is an abundant number, since it is smaller than the sum of its proper divisors (1895901740).

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

1516721320 is a wasteful number, since it uses less digits than its factorization.

1516721320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37918044 (or 37918040 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 1516721320 is about 38945.1064961954. The cubic root of 1516721320 is about 1148.9521191843.

Adding to 1516721320 its reverse (231276151), we get a palindrome (1747997471).

The spelling of 1516721320 in words is "one billion, five hundred sixteen million, seven hundred twenty-one thousand, three hundred twenty".