72221551566 has 32 divisors (see below), whose sum is σ = 145975915680. Its totient is φ = 23818530816.

The previous prime is 72221551561. The next prime is 72221551583. The reversal of 72221551566 is 66515512227.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72221551561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2141910 + ... + 2175366.

It is an arithmetic number, because the mean of its divisors is an integer number (4561747365).

Almost surely, 2^72221551566 is an apocalyptic number.

72221551566 is an abundant number, since it is smaller than the sum of its proper divisors (73754364114).

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

72221551566 is a wasteful number, since it uses less digits than its factorization.

72221551566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37268.

The product of its digits is 252000, while the sum is 42.

The spelling of 72221551566 in words is "seventy-two billion, two hundred twenty-one million, five hundred fifty-one thousand, five hundred sixty-six".