66110551 has 4 divisors (see below), whose sum is σ = 71195992. Its totient is φ = 61025112.

The previous prime is 66110549. The next prime is 66110587. The reversal of 66110551 is 15501166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15501166 = 2 ⋅7750583.

It is a cyclic number.

It is not a de Polignac number, because 66110551 - 2¹ = 66110549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66110521) 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, 2542701 + ... + 2542726.

It is an arithmetic number, because the mean of its divisors is an integer number (17798998).

Almost surely, 2^66110551 is an apocalyptic number.

66110551 is a deficient number, since it is larger than the sum of its proper divisors (5085441).

66110551 is a wasteful number, since it uses less digits than its factorization.

66110551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5085440.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 66110551 is about 8130.8395015521. The cubic root of 66110551 is about 404.3495141392.

The spelling of 66110551 in words is "sixty-six million, one hundred ten thousand, five hundred fifty-one".