690220418 has 4 divisors (see below), whose sum is σ = 1035330630. Its totient is φ = 345110208.

The previous prime is 690220411. The next prime is 690220423. The reversal of 690220418 is 814022096.

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., 595994569 + 94225849 = 24413^2 + 9707^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (690220411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172555103 + ... + 172555106.

Almost surely, 2^690220418 is an apocalyptic number.

690220418 is a deficient number, since it is larger than the sum of its proper divisors (345110212).

690220418 is a wasteful number, since it uses less digits than its factorization.

690220418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345110211.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 690220418 is about 26272.0463230408. The cubic root of 690220418 is about 883.7496757486.

The spelling of 690220418 in words is "six hundred ninety million, two hundred twenty thousand, four hundred eighteen".