221031634 has 4 divisors (see below), whose sum is σ = 331547454. Its totient is φ = 110515816.

The previous prime is 221031631. The next prime is 221031661. The reversal of 221031634 is 436130122.

221031634 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 436130122 = 2 ⋅218065061.

It can be written as a sum of positive squares in only one way, i.e., 198894609 + 22137025 = 14103^2 + 4705^2 .

It is not an unprimeable number, because it can be changed into a prime (221031631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55257907 + ... + 55257910.

Almost surely, 2^221031634 is an apocalyptic number.

221031634 is a deficient number, since it is larger than the sum of its proper divisors (110515820).

221031634 is a wasteful number, since it uses less digits than its factorization.

221031634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110515819.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 221031634 is about 14867.1326758054. The cubic root of 221031634 is about 604.6232054919.

Adding to 221031634 its reverse (436130122), we get a palindrome (657161756).

The spelling of 221031634 in words is "two hundred twenty-one million, thirty-one thousand, six hundred thirty-four".