72228919 has 4 divisors (see below), whose sum is σ = 82547344. Its totient is φ = 61910496.

The previous prime is 72228917. The next prime is 72228931. The reversal of 72228919 is 91982227.

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 72228919 - 2¹ = 72228917 is a prime.

It is a super-2 number, since 2×72228919² = 10434033479817122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72228913) 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, 5159202 + ... + 5159215.

It is an arithmetic number, because the mean of its divisors is an integer number (20636836).

Almost surely, 2^72228919 is an apocalyptic number.

72228919 is a deficient number, since it is larger than the sum of its proper divisors (10318425).

72228919 is a wasteful number, since it uses less digits than its factorization.

72228919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10318424.

The product of its digits is 36288, while the sum is 40.

The square root of 72228919 is about 8498.7598507076. The cubic root of 72228919 is about 416.4571969693.

The spelling of 72228919 in words is "seventy-two million, two hundred twenty-eight thousand, nine hundred nineteen".