66566552407 has 4 divisors (see below), whose sum is σ = 68365648456. Its totient is φ = 64767456360.

The previous prime is 66566552389. The next prime is 66566552419. The reversal of 66566552407 is 70425566566.

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

It is a cyclic number.

It is not a de Polignac number, because 66566552407 - 2¹⁹ = 66566028119 is a prime.

It is a super-2 number, since 2×66566552407² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66566553407) 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, 899547969 + ... + 899548042.

It is an arithmetic number, because the mean of its divisors is an integer number (17091412114).

Almost surely, 2^66566552407 is an apocalyptic number.

66566552407 is a deficient number, since it is larger than the sum of its proper divisors (1799096049).

66566552407 is a wasteful number, since it uses less digits than its factorization.

66566552407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1799096048.

The product of its (nonzero) digits is 9072000, while the sum is 52.

The spelling of 66566552407 in words is "sixty-six billion, five hundred sixty-six million, five hundred fifty-two thousand, four hundred seven".