66113161 has 9 divisors (see below), whose sum is σ = 67942471. Its totient is φ = 64332472.

The previous prime is 66113147. The next prime is 66113189. The reversal of 66113161 is 16131166.

The square root of 66113161 is 8131.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 60140025 + 5973136 = 7755^2 + 2444^2 .

It is not a de Polignac number, because 66113161 - 2²³ = 57724553 is a prime.

It is a Duffinian number.

66113161 is a Rhonda number in base 12.

It is not an unprimeable number, because it can be changed into a prime (66113261) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 382071 + ... + 382243.

Almost surely, 2^66113161 is an apocalyptic number.

66113161 is the 8131-st square number.

66113161 is the 4066-th centered octagonal number.

It is an amenable number.

66113161 is a deficient number, since it is larger than the sum of its proper divisors (1829310).

66113161 is an frugal number, since it uses more digits than its factorization.

66113161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440 (or 220 counting only the distinct ones).

The product of its digits is 648, while the sum is 25.

The cubic root of 66113161 is about 404.3548352179.

Multiplying 66113161 by its sum of digits (25), we get a square (1652829025 = 40655²).

The spelling of 66113161 in words is "sixty-six million, one hundred thirteen thousand, one hundred sixty-one".