1680428515 has 4 divisors (see below), whose sum is σ = 2016514224. Its totient is φ = 1344342808.

The previous prime is 1680428509. The next prime is 1680428521. The reversal of 1680428515 is 5158240861.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5158240861 = 17 ⋅303425933.

It is an interprime number because it is at equal distance from previous prime (1680428509) and next prime (1680428521).

It is a cyclic number.

It is not a de Polignac number, because 1680428515 - 2⁵ = 1680428483 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

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, 168042847 + ... + 168042856.

It is an arithmetic number, because the mean of its divisors is an integer number (504128556).

Almost surely, 2^1680428515 is an apocalyptic number.

1680428515 is a deficient number, since it is larger than the sum of its proper divisors (336085709).

1680428515 is an equidigital number, since it uses as much as digits as its factorization.

1680428515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336085708.

The product of its (nonzero) digits is 76800, while the sum is 40.

The square root of 1680428515 is about 40993.0300782950. The cubic root of 1680428515 is about 1188.8854557585.

The spelling of 1680428515 in words is "one billion, six hundred eighty million, four hundred twenty-eight thousand, five hundred fifteen".