72172747 has 4 divisors (see below), whose sum is σ = 72723816. Its totient is φ = 71621680.

The previous prime is 72172739. The next prime is 72172757. The reversal of 72172747 is 74727127.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 72172747 - 2³ = 72172739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72172717) 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, 275338 + ... + 275599.

It is an arithmetic number, because the mean of its divisors is an integer number (18180954).

Almost surely, 2^72172747 is an apocalyptic number.

72172747 is a deficient number, since it is larger than the sum of its proper divisors (551069).

72172747 is a wasteful number, since it uses less digits than its factorization.

72172747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 551068.

The product of its digits is 38416, while the sum is 37.

The square root of 72172747 is about 8495.4544904908. The cubic root of 72172747 is about 416.3492102106.

The spelling of 72172747 in words is "seventy-two million, one hundred seventy-two thousand, seven hundred forty-seven".