1688403145 has 24 divisors (see below), whose sum is σ = 2398337928. Its totient is φ = 1133468160.

The previous prime is 1688403131. The next prime is 1688403191. The reversal of 1688403145 is 5413048861.

It can be written as a sum of positive squares in 4 ways, for example, as 3136441 + 1685266704 = 1771^2 + 41052^2 .

It is not a de Polignac number, because 1688403145 - 2⁹ = 1688402633 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1688403098 and 1688403107.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 99472 + ... + 115201.

It is an arithmetic number, because the mean of its divisors is an integer number (99930747).

Almost surely, 2^1688403145 is an apocalyptic number.

It is an amenable number.

1688403145 is a deficient number, since it is larger than the sum of its proper divisors (709934783).

1688403145 is a wasteful number, since it uses less digits than its factorization.

1688403145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214713 (or 214702 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 40.

The square root of 1688403145 is about 41090.1830733327. The cubic root of 1688403145 is about 1190.7631441816.

The spelling of 1688403145 in words is "one billion, six hundred eighty-eight million, four hundred three thousand, one hundred forty-five".