72171293 has 2 divisors, whose sum is σ = 72171294. Its totient is φ = 72171292.

The previous prime is 72171283. The next prime is 72171299. The reversal of 72171293 is 39217127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54715609 + 17455684 = 7397^2 + 4178^2 .

It is an emirp because it is prime and its reverse (39217127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72171293 - 2⁴ = 72171277 is a prime.

It is equal to p_4238186 and since 72171293 and 4238186 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72171299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36085646 + 36085647.

It is an arithmetic number, because the mean of its divisors is an integer number (36085647).

Almost surely, 2^72171293 is an apocalyptic number.

It is an amenable number.

72171293 is a deficient number, since it is larger than the sum of its proper divisors (1).

72171293 is an equidigital number, since it uses as much as digits as its factorization.

72171293 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5292, while the sum is 32.

The square root of 72171293 is about 8495.3689148853. The cubic root of 72171293 is about 416.3464142530.

The spelling of 72171293 in words is "seventy-two million, one hundred seventy-one thousand, two hundred ninety-three".