66656426 has 8 divisors (see below), whose sum is σ = 100081380. Its totient is φ = 33295968.

The previous prime is 66656423. The next prime is 66656441. The reversal of 66656426 is 62465666.

It can be written as a sum of positive squares in 2 ways, for example, as 65626201 + 1030225 = 8101^2 + 1015^2 .

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

It is not an unprimeable number, because it can be changed into a prime (66656423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13451 + ... + 17726.

Almost surely, 2^66656426 is an apocalyptic number.

66656426 is a deficient number, since it is larger than the sum of its proper divisors (33424954).

66656426 is a wasteful number, since it uses less digits than its factorization.

66656426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32248.

The product of its digits is 311040, while the sum is 41.

The square root of 66656426 is about 8164.3386749938. The cubic root of 66656426 is about 405.4593700406.

The spelling of 66656426 in words is "sixty-six million, six hundred fifty-six thousand, four hundred twenty-six".