66546555507 has 32 divisors (see below), whose sum is σ = 99848582400. Its totient is φ = 43797666816.

The previous prime is 66546555503. The next prime is 66546555553. The reversal of 66546555507 is 70555564566.

It is not a de Polignac number, because 66546555507 - 2² = 66546555503 is a prime.

It is a super-4 number, since 4×66546555507⁴ (a number of 44 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (66546555503) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3259443 + ... + 3279795.

It is an arithmetic number, because the mean of its divisors is an integer number (3120268200).

Almost surely, 2^66546555507 is an apocalyptic number.

66546555507 is a deficient number, since it is larger than the sum of its proper divisors (33302026893).

66546555507 is a wasteful number, since it uses less digits than its factorization.

66546555507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21904 (or 21898 counting only the distinct ones).

The product of its (nonzero) digits is 18900000, while the sum is 54.

The spelling of 66546555507 in words is "sixty-six billion, five hundred forty-six million, five hundred fifty-five thousand, five hundred seven".