72166361 has 4 divisors (see below), whose sum is σ = 72214500. Its totient is φ = 72118224.

The previous prime is 72166333. The next prime is 72166363. The reversal of 72166361 is 16366127.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12645136 + 59521225 = 3556^2 + 7715^2 .

It is a cyclic number.

It is not a de Polignac number, because 72166361 - 2¹⁴ = 72149977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72166363) 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, 21746 + ... + 24843.

It is an arithmetic number, because the mean of its divisors is an integer number (18053625).

Almost surely, 2^72166361 is an apocalyptic number.

It is an amenable number.

72166361 is a deficient number, since it is larger than the sum of its proper divisors (48139).

72166361 is a wasteful number, since it uses less digits than its factorization.

72166361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48138.

The product of its digits is 9072, while the sum is 32.

The square root of 72166361 is about 8495.0786341269. The cubic root of 72166361 is about 416.3369300236.

It can be divided in two parts, 72166 and 361, that added together give a palindrome (72527).

The spelling of 72166361 in words is "seventy-two million, one hundred sixty-six thousand, three hundred sixty-one".