72172042 has 4 divisors (see below), whose sum is σ = 108258066. Its totient is φ = 36086020.

The previous prime is 72172033. The next prime is 72172043. The reversal of 72172042 is 24027127.

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

It can be written as a sum of positive squares in only one way, i.e., 54774801 + 17397241 = 7401^2 + 4171^2 .

It is a junction number, because it is equal to n+sod(n) for n = 72171998 and 72172016.

It is not an unprimeable number, because it can be changed into a prime (72172043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18043009 + ... + 18043012.

Almost surely, 2^72172042 is an apocalyptic number.

72172042 is a deficient number, since it is larger than the sum of its proper divisors (36086024).

72172042 is a wasteful number, since it uses less digits than its factorization.

72172042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36086023.

The product of its (nonzero) digits is 1568, while the sum is 25.

The square root of 72172042 is about 8495.4129976123. The cubic root of 72172042 is about 416.3478545412.

Adding to 72172042 its reverse (24027127), we get a palindrome (96199169).

The spelling of 72172042 in words is "seventy-two million, one hundred seventy-two thousand, forty-two".