221267561800 has 48 divisors (see below), whose sum is σ = 526994590500. Its totient is φ = 86348313600.

The previous prime is 221267561743. The next prime is 221267561803. The reversal of 221267561800 is 8165762122.

It can be written as a sum of positive squares in 6 ways, for example, as 81662206756 + 139605355044 = 285766^2 + 373638^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (221267561803) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13483725 + ... + 13500124.

Almost surely, 2^221267561800 is an apocalyptic number.

221267561800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221267561800 is an abundant number, since it is smaller than the sum of its proper divisors (305727028700).

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

221267561800 is a wasteful number, since it uses less digits than its factorization.

221267561800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26983906 (or 26983897 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 40.

The spelling of 221267561800 in words is "two hundred twenty-one billion, two hundred sixty-seven million, five hundred sixty-one thousand, eight hundred".