666640414 has 16 divisors (see below), whose sum is σ = 1155035376. Its totient is φ = 285193600.

The previous prime is 666640409. The next prime is 666640417. The reversal of 666640414 is 414046666.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666640417) 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, 890857 + ... + 891604.

It is an arithmetic number, because the mean of its divisors is an integer number (72189711).

Almost surely, 2^666640414 is an apocalyptic number.

666640414 is a deficient number, since it is larger than the sum of its proper divisors (488394962).

666640414 is a wasteful number, since it uses less digits than its factorization.

666640414 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1782491.

The product of its (nonzero) digits is 82944, while the sum is 37.

The square root of 666640414 is about 25819.3805890072. The cubic root of 666640414 is about 873.5689976774.

The spelling of 666640414 in words is "six hundred sixty-six million, six hundred forty thousand, four hundred fourteen".