1690168538 has 8 divisors (see below), whose sum is σ = 2535543540. Its totient is φ = 844987360.

The previous prime is 1690168531. The next prime is 1690168553. The reversal of 1690168538 is 8358610961.

It can be written as a sum of positive squares in 2 ways, for example, as 1464057169 + 226111369 = 38263^2 + 15037^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 1690168492 and 1690168501.

It is not an unprimeable number, because it can be changed into a prime (1690168531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24233 + ... + 62988.

Almost surely, 2^1690168538 is an apocalyptic number.

1690168538 is a deficient number, since it is larger than the sum of its proper divisors (845375002).

1690168538 is an equidigital number, since it uses as much as digits as its factorization.

1690168538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96912.

The product of its (nonzero) digits is 311040, while the sum is 47.

The square root of 1690168538 is about 41111.6593924400. The cubic root of 1690168538 is about 1191.1780199528.

The spelling of 1690168538 in words is "one billion, six hundred ninety million, one hundred sixty-eight thousand, five hundred thirty-eight".