72173737 has 4 divisors (see below), whose sum is σ = 73852240. Its totient is φ = 70495236.

The previous prime is 72173707. The next prime is 72173753. The reversal of 72173737 is 73737127.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 73737127 = 31 ⋅2378617.

It is a cyclic number.

It is not a de Polignac number, because 72173737 - 2¹⁹ = 71649449 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72173696 and 72173705.

It is not an unprimeable number, because it can be changed into a prime (72173707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 839187 + ... + 839272.

It is an arithmetic number, because the mean of its divisors is an integer number (18463060).

Almost surely, 2^72173737 is an apocalyptic number.

It is an amenable number.

72173737 is a deficient number, since it is larger than the sum of its proper divisors (1678503).

72173737 is a wasteful number, since it uses less digits than its factorization.

72173737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1678502.

The product of its digits is 43218, while the sum is 37.

The square root of 72173737 is about 8495.5127567440. The cubic root of 72173737 is about 416.3511139016.

The spelling of 72173737 in words is "seventy-two million, one hundred seventy-three thousand, seven hundred thirty-seven".