221258938 has 4 divisors (see below), whose sum is σ = 331888410. Its totient is φ = 110629468.

The previous prime is 221258929. The next prime is 221258957. The reversal of 221258938 is 839852122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 142635249 + 78623689 = 11943^2 + 8867^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 221258938.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55314733 + ... + 55314736.

Almost surely, 2^221258938 is an apocalyptic number.

221258938 is a deficient number, since it is larger than the sum of its proper divisors (110629472).

221258938 is a wasteful number, since it uses less digits than its factorization.

221258938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110629471.

The product of its digits is 69120, while the sum is 40.

The square root of 221258938 is about 14874.7752251925. The cubic root of 221258938 is about 604.8303948225.

The spelling of 221258938 in words is "two hundred twenty-one million, two hundred fifty-eight thousand, nine hundred thirty-eight".