66411865861534 has 4 divisors (see below), whose sum is σ = 99617798792304. Its totient is φ = 33205932930766.

The previous prime is 66411865861519. The next prime is 66411865861567. The reversal of 66411865861534 is 43516856811466.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16602966465382 + ... + 16602966465385.

It is an arithmetic number, because the mean of its divisors is an integer number (24904449698076).

Almost surely, 2^{66411865861534} is an apocalyptic number.

66411865861534 is a deficient number, since it is larger than the sum of its proper divisors (33205932930770).

66411865861534 is a wasteful number, since it uses less digits than its factorization.

66411865861534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33205932930769.

The product of its digits is 99532800, while the sum is 64.

The spelling of 66411865861534 in words is "sixty-six trillion, four hundred eleven billion, eight hundred sixty-five million, eight hundred sixty-one thousand, five hundred thirty-four".