72069221 has 4 divisors (see below), whose sum is σ = 82364832. Its totient is φ = 61773612.

The previous prime is 72069211. The next prime is 72069233. The reversal of 72069221 is 12296027.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72069221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72069211) 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, 5147795 + ... + 5147808.

It is an arithmetic number, because the mean of its divisors is an integer number (20591208).

Almost surely, 2^72069221 is an apocalyptic number.

It is an amenable number.

72069221 is a deficient number, since it is larger than the sum of its proper divisors (10295611).

72069221 is a wasteful number, since it uses less digits than its factorization.

72069221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10295610.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 72069221 is about 8489.3592808880. The cubic root of 72069221 is about 416.1500417995.

The spelling of 72069221 in words is "seventy-two million, sixty-nine thousand, two hundred twenty-one".