221510587660 has 96 divisors (see below), whose sum is σ = 485237874240. Its totient is φ = 84865228800.

The previous prime is 221510587657. The next prime is 221510587679. The reversal of 221510587660 is 66785015122.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42620182 + ... + 42625378.

It is an arithmetic number, because the mean of its divisors is an integer number (5054561190).

Almost surely, 2^221510587660 is an apocalyptic number.

221510587660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221510587660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242618937120).

221510587660 is an abundant number, since it is smaller than the sum of its proper divisors (263727286580).

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

221510587660 is a wasteful number, since it uses less digits than its factorization.

221510587660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6187 (or 6185 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 43.

The spelling of 221510587660 in words is "two hundred twenty-one billion, five hundred ten million, five hundred eighty-seven thousand, six hundred sixty".