221642458 has 4 divisors (see below), whose sum is σ = 332463690. Its totient is φ = 110821228.

The previous prime is 221642431. The next prime is 221642471. The reversal of 221642458 is 854246122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 854246122 = 2 ⋅427123061.

It can be written as a sum of positive squares in only one way, i.e., 140588449 + 81054009 = 11857^2 + 9003^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55410613 + ... + 55410616.

Almost surely, 2^221642458 is an apocalyptic number.

221642458 is a deficient number, since it is larger than the sum of its proper divisors (110821232).

221642458 is a wasteful number, since it uses less digits than its factorization.

221642458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110821231.

The product of its digits is 30720, while the sum is 34.

The square root of 221642458 is about 14887.6612669687. The cubic root of 221642458 is about 605.1796547718.

The spelling of 221642458 in words is "two hundred twenty-one million, six hundred forty-two thousand, four hundred fifty-eight".