221549402 has 4 divisors (see below), whose sum is σ = 332324106. Its totient is φ = 110774700.

The previous prime is 221549401. The next prime is 221549407. The reversal of 221549402 is 204945122.

221549402 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: 204945122 = 2 ⋅102472561.

It can be written as a sum of positive squares in only one way, i.e., 181467841 + 40081561 = 13471^2 + 6331^2 .

It is not an unprimeable number, because it can be changed into a prime (221549401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55387349 + ... + 55387352.

Almost surely, 2^221549402 is an apocalyptic number.

221549402 is a deficient number, since it is larger than the sum of its proper divisors (110774704).

221549402 is a wasteful number, since it uses less digits than its factorization.

221549402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110774703.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 221549402 is about 14884.5356662544. The cubic root of 221549402 is about 605.0949485568.

The spelling of 221549402 in words is "two hundred twenty-one million, five hundred forty-nine thousand, four hundred two".