6690400 has 36 divisors (see below), whose sum is σ = 16334892. Its totient is φ = 2675840.

The previous prime is 6690379. The next prime is 6690427. The reversal of 6690400 is 40966.

It is a super-2 number, since 2×6690400² = 89522904320000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3382 + ... + 4981.

It is an arithmetic number, because the mean of its divisors is an integer number (453747).

Almost surely, 2^6690400 is an apocalyptic number.

It is an amenable number.

6690400 is an abundant number, since it is smaller than the sum of its proper divisors (9644492).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6690400 is a wasteful number, since it uses less digits than its factorization.

6690400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8383 (or 8370 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 6690400 is about 2586.5807545870. The cubic root of 6690400 is about 188.4302804875.

The spelling of 6690400 in words is "six million, six hundred ninety thousand, four hundred".