221561494 has 32 divisors (see below), whose sum is σ = 415201536. Its totient is φ = 86145120.

The previous prime is 221561467. The next prime is 221561503. The reversal of 221561494 is 494165122.

221561494 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 93229 + ... + 95575.

It is an arithmetic number, because the mean of its divisors is an integer number (12975048).

Almost surely, 2^221561494 is an apocalyptic number.

221561494 is a deficient number, since it is larger than the sum of its proper divisors (193640042).

221561494 is a wasteful number, since it uses less digits than its factorization.

221561494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2980.

The product of its digits is 17280, while the sum is 34.

The square root of 221561494 is about 14884.9418541021. The cubic root of 221561494 is about 605.1059568992.

The spelling of 221561494 in words is "two hundred twenty-one million, five hundred sixty-one thousand, four hundred ninety-four".