221777164 has 12 divisors (see below), whose sum is σ = 443554384. Its totient is φ = 95047344.

The previous prime is 221777147. The next prime is 221777183. The reversal of 221777164 is 461777122.

221777164 is an admirable number.

It is a super-2 number, since 2×221777164² = 98370220943765792, which contains 22 as substring.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3960279 + ... + 3960334.

Almost surely, 2^221777164 is an apocalyptic number.

It is an amenable number.

221777164 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

221777164 is a wasteful number, since it uses less digits than its factorization.

221777164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7920624 (or 7920622 counting only the distinct ones).

The product of its digits is 32928, while the sum is 37.

The square root of 221777164 is about 14892.1846617613. The cubic root of 221777164 is about 605.3022317992.

The spelling of 221777164 in words is "two hundred twenty-one million, seven hundred seventy-seven thousand, one hundred sixty-four".