6403661 has 8 divisors (see below), whose sum is σ = 7075200. Its totient is φ = 5747040.

The previous prime is 6403651. The next prime is 6403681. The reversal of 6403661 is 1663046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6403661 is a prime.

It is a zygodrome in base 3.

It is a self number, because there is not a number n which added to its sum of digits gives 6403661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6403601) 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, 2816 + ... + 4553.

It is an arithmetic number, because the mean of its divisors is an integer number (884400).

Almost surely, 2^6403661 is an apocalyptic number.

It is an amenable number.

6403661 is a deficient number, since it is larger than the sum of its proper divisors (671539).

6403661 is a wasteful number, since it uses less digits than its factorization.

6403661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7459.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 6403661 is about 2530.5455933454. The cubic root of 6403661 is about 185.6989483812.

The spelling of 6403661 in words is "six million, four hundred three thousand, six hundred sixty-one".