221996970 has 64 divisors (see below), whose sum is σ = 637539840. Its totient is φ = 54644544.

The previous prime is 221996939. The next prime is 221996977. The reversal of 221996970 is 79699122.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221996977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28114 + ... + 35133.

It is an arithmetic number, because the mean of its divisors is an integer number (9961560).

Almost surely, 2^221996970 is an apocalyptic number.

221996970 is an abundant number, since it is smaller than the sum of its proper divisors (415542870).

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

221996970 is a wasteful number, since it uses less digits than its factorization.

221996970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63276 (or 63270 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 221996970 is about 14899.5627452620. The cubic root of 221996970 is about 605.5021398641.

The spelling of 221996970 in words is "two hundred twenty-one million, nine hundred ninety-six thousand, nine hundred seventy".