219430661 has 4 divisors (see below), whose sum is σ = 220903500. Its totient is φ = 217957824.

The previous prime is 219430643. The next prime is 219430667. The reversal of 219430661 is 166034912.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 57988225 + 161442436 = 7615^2 + 12706^2 .

It is a cyclic number.

It is not a de Polignac number, because 219430661 - 2²⁶ = 152321797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (219430667) 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 3 ways as a sum of consecutive naturals, for example, 736196 + ... + 736493.

It is an arithmetic number, because the mean of its divisors is an integer number (55225875).

Almost surely, 2^219430661 is an apocalyptic number.

It is an amenable number.

219430661 is a deficient number, since it is larger than the sum of its proper divisors (1472839).

219430661 is a wasteful number, since it uses less digits than its factorization.

219430661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1472838.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 219430661 is about 14813.1921272898. The cubic root of 219430661 is about 603.1598674787.

The spelling of 219430661 in words is "two hundred nineteen million, four hundred thirty thousand, six hundred sixty-one".