72031181 has 2 divisors, whose sum is σ = 72031182. Its totient is φ = 72031180.

The previous prime is 72031163. The next prime is 72031199. The reversal of 72031181 is 18113027.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (72031163) and next prime (72031199).

It can be written as a sum of positive squares in only one way, i.e., 59428681 + 12602500 = 7709^2 + 3550^2 .

It is an emirp because it is prime and its reverse (18113027) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72031181 is a prime.

It is a super-2 number, since 2×72031181² = 10376982072509522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72031111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36015590 + 36015591.

It is an arithmetic number, because the mean of its divisors is an integer number (36015591).

Almost surely, 2^72031181 is an apocalyptic number.

It is an amenable number.

72031181 is a deficient number, since it is larger than the sum of its proper divisors (1).

72031181 is an equidigital number, since it uses as much as digits as its factorization.

72031181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 72031181 is about 8487.1185334011. The cubic root of 72031181 is about 416.0768106596.

The spelling of 72031181 in words is "seventy-two million, thirty-one thousand, one hundred eighty-one".