666402441 has 4 divisors (see below), whose sum is σ = 888536592. Its totient is φ = 444268292.

The previous prime is 666402419. The next prime is 666402461. The reversal of 666402441 is 144204666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 666402441 - 2⁶ = 666402377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (666402461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111067071 + ... + 111067076.

It is an arithmetic number, because the mean of its divisors is an integer number (222134148).

Almost surely, 2^666402441 is an apocalyptic number.

It is an amenable number.

666402441 is a deficient number, since it is larger than the sum of its proper divisors (222134151).

666402441 is a wasteful number, since it uses less digits than its factorization.

666402441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222134150.

The product of its (nonzero) digits is 27648, while the sum is 33.

The square root of 666402441 is about 25814.7717595953. The cubic root of 666402441 is about 873.4650382953.

The spelling of 666402441 in words is "six hundred sixty-six million, four hundred two thousand, four hundred forty-one".