72226161 has 24 divisors (see below), whose sum is σ = 123649344. Its totient is φ = 41271120.

The previous prime is 72226157. The next prime is 72226171. The reversal of 72226161 is 16162227.

It is not a de Polignac number, because 72226161 - 2² = 72226157 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72226151) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19530 + ... + 22931.

It is an arithmetic number, because the mean of its divisors is an integer number (5152056).

Almost surely, 2^72226161 is an apocalyptic number.

It is an amenable number.

72226161 is a deficient number, since it is larger than the sum of its proper divisors (51423183).

72226161 is an equidigital number, since it uses as much as digits as its factorization.

72226161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42483 (or 42471 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 72226161 is about 8498.5975901910. The cubic root of 72226161 is about 416.4518962136.

Adding to 72226161 its reverse (16162227), we get a palindrome (88388388).

The spelling of 72226161 in words is "seventy-two million, two hundred twenty-six thousand, one hundred sixty-one".