209061988 has 24 divisors (see below), whose sum is σ = 397854072. Its totient is φ = 95721984.

The previous prime is 209061967. The next prime is 209061989. The reversal of 209061988 is 889160902.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 94828644 + 114233344 = 9738^2 + 10688^2 .

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (209061989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39031 + ... + 44062.

It is an arithmetic number, because the mean of its divisors is an integer number (16577253).

Almost surely, 2^209061988 is an apocalyptic number.

It is an amenable number.

209061988 is a deficient number, since it is larger than the sum of its proper divisors (188792084).

209061988 is a wasteful number, since it uses less digits than its factorization.

209061988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83151 (or 83149 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 43.

The square root of 209061988 is about 14458.9760356673. The cubic root of 209061988 is about 593.5058790633.

The spelling of 209061988 in words is "two hundred nine million, sixty-one thousand, nine hundred eighty-eight".