221958810640 has 40 divisors (see below), whose sum is σ = 589776269760. Its totient is φ = 76100163456.

The previous prime is 221958810629. The next prime is 221958810691. The reversal of 221958810640 is 46018859122.

It is a tau number, because it is divible by the number of its divisors (40).

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, 198176950 + ... + 198178069.

It is an arithmetic number, because the mean of its divisors is an integer number (14744406744).

Almost surely, 2^221958810640 is an apocalyptic number.

221958810640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221958810640 is an abundant number, since it is smaller than the sum of its proper divisors (367817459120).

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

221958810640 is a wasteful number, since it uses less digits than its factorization.

221958810640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396355039 (or 396355033 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 46.

The spelling of 221958810640 in words is "two hundred twenty-one billion, nine hundred fifty-eight million, eight hundred ten thousand, six hundred forty".