72221784 has 16 divisors (see below), whose sum is σ = 180554520. Its totient is φ = 24073920.

The previous prime is 72221783. The next prime is 72221789. The reversal of 72221784 is 48712227.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72221783) 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, 1504597 + ... + 1504644.

Almost surely, 2^72221784 is an apocalyptic number.

It is an amenable number.

72221784 is an abundant number, since it is smaller than the sum of its proper divisors (108332736).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72221784 is a wasteful number, since it uses less digits than its factorization.

72221784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3009250 (or 3009246 counting only the distinct ones).

The product of its digits is 12544, while the sum is 33.

The square root of 72221784 is about 8498.3400732143. The cubic root of 72221784 is about 416.4434835334.

The spelling of 72221784 in words is "seventy-two million, two hundred twenty-one thousand, seven hundred eighty-four".