666426 has 16 divisors (see below), whose sum is σ = 1346400. Its totient is φ = 219888.

The previous prime is 666403. The next prime is 666427. The reversal of 666426 is 624666.

666426 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×666426² = 888247226952, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 666393 and 666402.

It is not an unprimeable number, because it can be changed into a prime (666427) 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, 145 + ... + 1163.

It is an arithmetic number, because the mean of its divisors is an integer number (84150).

2⁶⁶⁶⁴²⁶ is an apocalyptic number.

666426 is an abundant number, since it is smaller than the sum of its proper divisors (679974).

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

666426 is a wasteful number, since it uses less digits than its factorization.

666426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1133.

The product of its digits is 10368, while the sum is 30.

The square root of 666426 is about 816.3491899916. The cubic root of 666426 is about 87.3475331235.

The spelling of 666426 in words is "six hundred sixty-six thousand, four hundred twenty-six".