66685654 has 16 divisors (see below), whose sum is σ = 115452576. Its totient is φ = 28296000.

The previous prime is 66685637. The next prime is 66685693. The reversal of 66685654 is 45658666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22167 + ... + 24994.

It is an arithmetic number, because the mean of its divisors is an integer number (7215786).

Almost surely, 2^66685654 is an apocalyptic number.

66685654 is a deficient number, since it is larger than the sum of its proper divisors (48766922).

66685654 is a wasteful number, since it uses less digits than its factorization.

66685654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47271.

The product of its digits is 1036800, while the sum is 46.

The square root of 66685654 is about 8166.1284584557. The cubic root of 66685654 is about 405.5186243165.

It can be divided in two parts, 666 and 85654, that added together give a triangular number (86320 = T₄₁₅).

The spelling of 66685654 in words is "sixty-six million, six hundred eighty-five thousand, six hundred fifty-four".