690018386 has 4 divisors (see below), whose sum is σ = 1035027582. Its totient is φ = 345009192.

The previous prime is 690018349. The next prime is 690018403. The reversal of 690018386 is 683810096.

It is a happy number.

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., 441798361 + 248220025 = 21019^2 + 15755^2 .

It is a super-2 number, since 2×690018386² = 952250746036089992, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172504595 + ... + 172504598.

Almost surely, 2^690018386 is an apocalyptic number.

690018386 is a deficient number, since it is larger than the sum of its proper divisors (345009196).

690018386 is a wasteful number, since it uses less digits than its factorization.

690018386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345009195.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 690018386 is about 26268.2010423249. The cubic root of 690018386 is about 883.6634409106.

The spelling of 690018386 in words is "six hundred ninety million, eighteen thousand, three hundred eighty-six".