72672221 has 8 divisors (see below), whose sum is σ = 73773504. Its totient is φ = 71579200.

The previous prime is 72672209. The next prime is 72672241. The reversal of 72672221 is 12227627.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 72672221 - 2¹⁰ = 72671197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72672241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16946 + ... + 20796.

It is an arithmetic number, because the mean of its divisors is an integer number (9221688).

Almost surely, 2^72672221 is an apocalyptic number.

It is an amenable number.

72672221 is a deficient number, since it is larger than the sum of its proper divisors (1101283).

72672221 is a wasteful number, since it uses less digits than its factorization.

72672221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4131.

The product of its digits is 4704, while the sum is 29.

The square root of 72672221 is about 8524.8003495683. The cubic root of 72672221 is about 417.3074561259.

Adding to 72672221 its reverse (12227627), we get a palindrome (84899848).

The spelling of 72672221 in words is "seventy-two million, six hundred seventy-two thousand, two hundred twenty-one".