6661403 has 8 divisors (see below), whose sum is σ = 7768800. Its totient is φ = 5709480.

The previous prime is 6661379. The next prime is 6661409. The reversal of 6661403 is 3041666.

It is not a de Polignac number, because 6661403 - 2¹⁴ = 6645019 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6661409) 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, 9368 + ... + 10053.

It is an arithmetic number, because the mean of its divisors is an integer number (971100).

Almost surely, 2^6661403 is an apocalyptic number.

6661403 is a deficient number, since it is larger than the sum of its proper divisors (1107397).

6661403 is an equidigital number, since it uses as much as digits as its factorization.

6661403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19442 (or 19428 counting only the distinct ones).

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

The square root of 6661403 is about 2580.9693915271. The cubic root of 6661403 is about 188.1576597345.

The spelling of 6661403 in words is "six million, six hundred sixty-one thousand, four hundred three".