72205237 has 4 divisors (see below), whose sum is σ = 77759500. Its totient is φ = 66650976.

The previous prime is 72205219. The next prime is 72205247. The reversal of 72205237 is 73250227.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73250227 = 907 ⋅80761.

It can be written as a sum of positive squares in 2 ways, for example, as 24512401 + 47692836 = 4951^2 + 6906^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72205237 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72205247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2777112 + ... + 2777137.

It is an arithmetic number, because the mean of its divisors is an integer number (19439875).

Almost surely, 2^72205237 is an apocalyptic number.

It is an amenable number.

72205237 is a deficient number, since it is larger than the sum of its proper divisors (5554263).

72205237 is a wasteful number, since it uses less digits than its factorization.

72205237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5554262.

The product of its (nonzero) digits is 5880, while the sum is 28.

The square root of 72205237 is about 8497.3664743849. The cubic root of 72205237 is about 416.4116768020.

The spelling of 72205237 in words is "seventy-two million, two hundred five thousand, two hundred thirty-seven".