72161473 has 4 divisors (see below), whose sum is σ = 72375940. Its totient is φ = 71947008.

The previous prime is 72161431. The next prime is 72161477. The reversal of 72161473 is 37416127.

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

It can be written as a sum of positive squares in 2 ways, for example, as 7969329 + 64192144 = 2823^2 + 8012^2 .

It is a cyclic number.

It is not a de Polignac number, because 72161473 - 2¹³ = 72153281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72161477) 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, 106728 + ... + 107401.

It is an arithmetic number, because the mean of its divisors is an integer number (18093985).

Almost surely, 2^72161473 is an apocalyptic number.

It is an amenable number.

72161473 is a deficient number, since it is larger than the sum of its proper divisors (214467).

72161473 is a wasteful number, since it uses less digits than its factorization.

72161473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214466.

The product of its digits is 7056, while the sum is 31.

The square root of 72161473 is about 8494.7909332720. The cubic root of 72161473 is about 416.3275299798.

The spelling of 72161473 in words is "seventy-two million, one hundred sixty-one thousand, four hundred seventy-three".