66517819874 has 16 divisors (see below), whose sum is σ = 108900797760. Its totient is φ = 30220523760.

The previous prime is 66517819871. The next prime is 66517819897. The reversal of 66517819874 is 47891871566.

It is not an unprimeable number, because it can be changed into a prime (66517819871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 696569 + ... + 786284.

It is an arithmetic number, because the mean of its divisors is an integer number (6806299860).

Almost surely, 2^66517819874 is an apocalyptic number.

66517819874 is a deficient number, since it is larger than the sum of its proper divisors (42382977886).

66517819874 is a wasteful number, since it uses less digits than its factorization.

66517819874 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1484905.

The product of its digits is 20321280, while the sum is 62.

The spelling of 66517819874 in words is "sixty-six billion, five hundred seventeen million, eight hundred nineteen thousand, eight hundred seventy-four".