72171149 has 2 divisors, whose sum is σ = 72171150. Its totient is φ = 72171148.

The previous prime is 72171133. The next prime is 72171167. The reversal of 72171149 is 94117127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51984100 + 20187049 = 7210^2 + 4493^2 .

It is a cyclic number.

It is not a de Polignac number, because 72171149 - 2⁴ = 72171133 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72171109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36085574 + 36085575.

It is an arithmetic number, because the mean of its divisors is an integer number (36085575).

Almost surely, 2^72171149 is an apocalyptic number.

It is an amenable number.

72171149 is a deficient number, since it is larger than the sum of its proper divisors (1).

72171149 is an equidigital number, since it uses as much as digits as its factorization.

72171149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3528, while the sum is 32.

The square root of 72171149 is about 8495.3604396753. The cubic root of 72171149 is about 416.3461373473.

The spelling of 72171149 in words is "seventy-two million, one hundred seventy-one thousand, one hundred forty-nine".