221709130 has 16 divisors (see below), whose sum is σ = 399435624. Its totient is φ = 88603840.

The previous prime is 221709127. The next prime is 221709133. The reversal of 221709130 is 31907122.

It is an interprime number because it is at equal distance from previous prime (221709127) and next prime (221709133).

It can be written as a sum of positive squares in 4 ways, for example, as 216001809 + 5707321 = 14697^2 + 2389^2 .

It is a junction number, because it is equal to n+sod(n) for n = 221709095 and 221709104.

It is not an unprimeable number, because it can be changed into a prime (221709133) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2424 + ... + 21196.

Almost surely, 2^221709130 is an apocalyptic number.

221709130 is a deficient number, since it is larger than the sum of its proper divisors (177726494).

221709130 is a wasteful number, since it uses less digits than its factorization.

221709130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19961.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 221709130 is about 14889.9002683027. The cubic root of 221709130 is about 605.2403298086.

It can be divided in two parts, 2217091 and 30, that added together give a square (2217121 = 1489²).

The spelling of 221709130 in words is "two hundred twenty-one million, seven hundred nine thousand, one hundred thirty".