72179969 has 2 divisors, whose sum is σ = 72179970. Its totient is φ = 72179968.

The previous prime is 72179903. The next prime is 72179981. The reversal of 72179969 is 96997127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55696369 + 16483600 = 7463^2 + 4060^2 .

It is an emirp because it is prime and its reverse (96997127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72179969 - 2⁸ = 72179713 is a prime.

It is a super-2 number, since 2×72179969² = 10419895849681922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (72179669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36089984 + 36089985.

It is an arithmetic number, because the mean of its divisors is an integer number (36089985).

Almost surely, 2^72179969 is an apocalyptic number.

It is an amenable number.

72179969 is a deficient number, since it is larger than the sum of its proper divisors (1).

72179969 is an equidigital number, since it uses as much as digits as its factorization.

72179969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 428652, while the sum is 50.

The square root of 72179969 is about 8495.8795306902. The cubic root of 72179969 is about 416.3630971408.

The spelling of 72179969 in words is "seventy-two million, one hundred seventy-nine thousand, nine hundred sixty-nine".