72165637 has 2 divisors, whose sum is σ = 72165638. Its totient is φ = 72165636.

The previous prime is 72165581. The next prime is 72165641. The reversal of 72165637 is 73656127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53494596 + 18671041 = 7314^2 + 4321^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72165637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72165596 and 72165605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72165647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36082818 + 36082819.

It is an arithmetic number, because the mean of its divisors is an integer number (36082819).

Almost surely, 2^72165637 is an apocalyptic number.

It is an amenable number.

72165637 is a deficient number, since it is larger than the sum of its proper divisors (1).

72165637 is an equidigital number, since it uses as much as digits as its factorization.

72165637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52920, while the sum is 37.

The square root of 72165637 is about 8495.0360211126. The cubic root of 72165637 is about 416.3355377362.

The spelling of 72165637 in words is "seventy-two million, one hundred sixty-five thousand, six hundred thirty-seven".