66666604429 has 4 divisors (see below), whose sum is σ = 66706550140. Its totient is φ = 66626658720.

The previous prime is 66666604423. The next prime is 66666604513. The reversal of 66666604429 is 92440666666.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20313375625 + 46353228804 = 142525^2 + 215298^2 .

It is a cyclic number.

It is not a de Polignac number, because 66666604429 - 2⁵ = 66666604397 is a prime.

It is a super-2 number, since 2×66666604429² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66666604429.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66666604423) 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, 19970352 + ... + 19973689.

It is an arithmetic number, because the mean of its divisors is an integer number (16676637535).

Almost surely, 2^66666604429 is an apocalyptic number.

It is an amenable number.

66666604429 is a deficient number, since it is larger than the sum of its proper divisors (39945711).

66666604429 is a wasteful number, since it uses less digits than its factorization.

66666604429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39945710.

The product of its (nonzero) digits is 13436928, while the sum is 55.

The spelling of 66666604429 in words is "sixty-six billion, six hundred sixty-six million, six hundred four thousand, four hundred twenty-nine".