66555550516 has 48 divisors (see below), whose sum is σ = 144093316864. Its totient is φ = 26193217536.

The previous prime is 66555550513. The next prime is 66555550519. The reversal of 66555550516 is 61505555566.

It is an interprime number because it is at equal distance from previous prime (66555550513) and next prime (66555550519).

It is a self number, because there is not a number n which added to its sum of digits gives 66555550516.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66555550513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 403440 + ... + 543943.

Almost surely, 2^66555550516 is an apocalyptic number.

It is an amenable number.

66555550516 is an abundant number, since it is smaller than the sum of its proper divisors (77537766348).

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

66555550516 is a wasteful number, since it uses less digits than its factorization.

66555550516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 947600 (or 947598 counting only the distinct ones).

The product of its (nonzero) digits is 3375000, while the sum is 49.

The spelling of 66555550516 in words is "sixty-six billion, five hundred fifty-five million, five hundred fifty thousand, five hundred sixteen".