66640026 has 8 divisors (see below), whose sum is σ = 133280064. Its totient is φ = 22213340.

The previous prime is 66640019. The next prime is 66640043. The reversal of 66640026 is 62004666.

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

66640026 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 66639975 and 66640002.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5553330 + ... + 5553341.

It is an arithmetic number, because the mean of its divisors is an integer number (16660008).

Almost surely, 2^66640026 is an apocalyptic number.

66640026 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

66640026 is a wasteful number, since it uses less digits than its factorization.

66640026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11106676.

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

The square root of 66640026 is about 8163.3342452701. The cubic root of 66640026 is about 405.4261145368.

The spelling of 66640026 in words is "sixty-six million, six hundred forty thousand, twenty-six".