221851918116 has 24 divisors (see below), whose sum is σ = 575171639840. Its totient is φ = 73950639336.

The previous prime is 221851918081. The next prime is 221851918121. The reversal of 221851918116 is 611819158122.

221851918116 is a `hidden beast` number, since 2 + 2 + 1 + 8 + 519 + 18 + 116 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1027092106 + ... + 1027092321.

Almost surely, 2^221851918116 is an apocalyptic number.

It is an amenable number.

221851918116 is an abundant number, since it is smaller than the sum of its proper divisors (353319721724).

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

221851918116 is a wasteful number, since it uses less digits than its factorization.

221851918116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2054184440 (or 2054184432 counting only the distinct ones).

The product of its digits is 69120, while the sum is 45.

The spelling of 221851918116 in words is "two hundred twenty-one billion, eight hundred fifty-one million, nine hundred eighteen thousand, one hundred sixteen".