690816818 has 4 divisors (see below), whose sum is σ = 1036225230. Its totient is φ = 345408408.

The previous prime is 690816793. The next prime is 690816823. The reversal of 690816818 is 818618096.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 683456449 + 7360369 = 26143^2 + 2713^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172704203 + ... + 172704206.

Almost surely, 2^690816818 is an apocalyptic number.

690816818 is a deficient number, since it is larger than the sum of its proper divisors (345408412).

690816818 is a wasteful number, since it uses less digits than its factorization.

690816818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345408411.

The product of its (nonzero) digits is 165888, while the sum is 47.

The square root of 690816818 is about 26283.3943393923. The cubic root of 690816818 is about 884.0041435280.

The spelling of 690816818 in words is "six hundred ninety million, eight hundred sixteen thousand, eight hundred eighteen".