221600879378 has 18 divisors (see below), whose sum is σ = 335167138773. Its totient is φ = 109886054040.

The previous prime is 221600879359. The next prime is 221600879441. The reversal of 221600879378 is 873978006122.

It can be written as a sum of positive squares in 2 ways, for example, as 195216399889 + 26384479489 = 441833^2 + 162433^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=332867.

It is a super-2 number, since 2×221600879378² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 84546908 + ... + 84549528.

Almost surely, 2^221600879378 is an apocalyptic number.

221600879378 is a deficient number, since it is larger than the sum of its proper divisors (113566259395).

221600879378 is an frugal number, since it uses more digits than its factorization.

221600879378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5498 (or 2750 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 53.

The spelling of 221600879378 in words is "two hundred twenty-one billion, six hundred million, eight hundred seventy-nine thousand, three hundred seventy-eight".