72345181 has 2 divisors, whose sum is σ = 72345182. Its totient is φ = 72345180.

The previous prime is 72345113. The next prime is 72345187. The reversal of 72345181 is 18154327.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58905625 + 13439556 = 7675^2 + 3666^2 .

It is an emirp because it is prime and its reverse (18154327) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72345181 - 2²⁵ = 38790749 is a prime.

It is a super-2 number, since 2×72345181² = 10467650427845522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72345187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36172590 + 36172591.

It is an arithmetic number, because the mean of its divisors is an integer number (36172591).

Almost surely, 2^72345181 is an apocalyptic number.

It is an amenable number.

72345181 is a deficient number, since it is larger than the sum of its proper divisors (1).

72345181 is an equidigital number, since it uses as much as digits as its factorization.

72345181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6720, while the sum is 31.

The square root of 72345181 is about 8505.5970395969. The cubic root of 72345181 is about 416.6805248369.

The spelling of 72345181 in words is "seventy-two million, three hundred forty-five thousand, one hundred eighty-one".