6688490 has 16 divisors (see below), whose sum is σ = 12365352. Its totient is φ = 2602944.

The previous prime is 6688481. The next prime is 6688499. The reversal of 6688490 is 948866.

It is an interprime number because it is at equal distance from previous prime (6688481) and next prime (6688499).

It can be written as a sum of positive squares in 4 ways, for example, as 6651241 + 37249 = 2579^2 + 193^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6688499) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8669 + ... + 9408.

Almost surely, 2^6688490 is an apocalyptic number.

6688490 is a deficient number, since it is larger than the sum of its proper divisors (5676862).

6688490 is a wasteful number, since it uses less digits than its factorization.

6688490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18121.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 6688490 is about 2586.2115149384. The cubic root of 6688490 is about 188.4123475243.

The spelling of 6688490 in words is "six million, six hundred eighty-eight thousand, four hundred ninety".