66161511 has 12 divisors (see below), whose sum is σ = 102918088. Its totient is φ = 40714704.

The previous prime is 66161507. The next prime is 66161519. The reversal of 66161511 is 11516166.

It is not a de Polignac number, because 66161511 - 2² = 66161507 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66161519) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 282625 + ... + 282858.

Almost surely, 2^66161511 is an apocalyptic number.

66161511 is a deficient number, since it is larger than the sum of its proper divisors (36756577).

66161511 is a wasteful number, since it uses less digits than its factorization.

66161511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 565502 (or 565499 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 66161511 is about 8133.9726456388. The cubic root of 66161511 is about 404.4533823756.

Adding to 66161511 its reverse (11516166), we get a palindrome (77677677).

The spelling of 66161511 in words is "sixty-six million, one hundred sixty-one thousand, five hundred eleven".