66691654 has 8 divisors (see below), whose sum is σ = 100306800. Its totient is φ = 33256056.

The previous prime is 66691643. The next prime is 66691657. The reversal of 66691654 is 45619666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 66691654.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66691657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43954 + ... + 45445.

It is an arithmetic number, because the mean of its divisors is an integer number (12538350).

Almost surely, 2^66691654 is an apocalyptic number.

66691654 is a deficient number, since it is larger than the sum of its proper divisors (33615146).

66691654 is a wasteful number, since it uses less digits than its factorization.

66691654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89774.

The product of its digits is 233280, while the sum is 43.

The square root of 66691654 is about 8166.4958213422. The cubic root of 66691654 is about 405.5307860466.

The spelling of 66691654 in words is "sixty-six million, six hundred ninety-one thousand, six hundred fifty-four".