7216571721660 has 96 divisors (see below), whose sum is σ = 23145158840832. Its totient is φ = 1645778584320.

The previous prime is 7216571721659. The next prime is 7216571721661. The reversal of 7216571721660 is 661271756127.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (7216571721659) and next prime (7216571721661).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7216571721661) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19207071 + ... + 19579190.

It is an arithmetic number, because the mean of its divisors is an integer number (241095404592).

Almost surely, 2^{7216571721660} is an apocalyptic number.

7216571721660 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

7216571721660 is an abundant number, since it is smaller than the sum of its proper divisors (15928587119172).

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

7216571721660 is a wasteful number, since it uses less digits than its factorization.

7216571721660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38786723 (or 38786721 counting only the distinct ones).

The product of its (nonzero) digits is 1481760, while the sum is 51.

The spelling of 7216571721660 in words is "seven trillion, two hundred sixteen billion, five hundred seventy-one million, seven hundred twenty-one thousand, six hundred sixty".