221992356865 has 8 divisors (see below), whose sum is σ = 270757891368. Its totient is φ = 174682510080.

The previous prime is 221992356851. The next prime is 221992356877. The reversal of 221992356865 is 568653299122.

It can be written as a sum of positive squares in 4 ways, for example, as 33917483889 + 188074872976 = 184167^2 + 433676^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221992356865 - 2⁹ = 221992356353 is a prime.

It is a Duffinian number.

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, 363921592 + ... + 363922201.

It is an arithmetic number, because the mean of its divisors is an integer number (33844736421).

Almost surely, 2^221992356865 is an apocalyptic number.

It is an amenable number.

221992356865 is a deficient number, since it is larger than the sum of its proper divisors (48765534503).

221992356865 is an equidigital number, since it uses as much as digits as its factorization.

221992356865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 727843859.

The product of its digits is 13996800, while the sum is 58.

The spelling of 221992356865 in words is "two hundred twenty-one billion, nine hundred ninety-two million, three hundred fifty-six thousand, eight hundred sixty-five".