66888056497 has 4 divisors (see below), whose sum is σ = 66888573760. Its totient is φ = 66887539236.

The previous prime is 66888056489. The next prime is 66888056509. The reversal of 66888056497 is 79465088866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 79465088866 = 2 ⋅39732544433.

It is a cyclic number.

It is not a de Polignac number, because 66888056497 - 2³ = 66888056489 is a prime.

It is a super-2 number, since 2×66888056497² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66888056407) 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, 127228 + ... + 387250.

It is an arithmetic number, because the mean of its divisors is an integer number (16722143440).

Almost surely, 2^66888056497 is an apocalyptic number.

It is an amenable number.

66888056497 is a deficient number, since it is larger than the sum of its proper divisors (517263).

66888056497 is a wasteful number, since it uses less digits than its factorization.

66888056497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517262.

The product of its (nonzero) digits is 139345920, while the sum is 67.

The spelling of 66888056497 in words is "sixty-six billion, eight hundred eighty-eight million, fifty-six thousand, four hundred ninety-seven".