919969209 has 6 divisors (see below), whose sum is σ = 1328844426. Its totient is φ = 613312800.

The previous prime is 919969199. The next prime is 919969277. The reversal of 919969209 is 902969919.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 516561984 + 403407225 = 22728^2 + 20085^2 .

It is not a de Polignac number, because 919969209 - 2¹¹ = 919967161 is a prime.

It is not an unprimeable number, because it can be changed into a prime (919969009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 51109392 + ... + 51109409.

It is an arithmetic number, because the mean of its divisors is an integer number (221474071).

Almost surely, 2^919969209 is an apocalyptic number.

It is an amenable number.

919969209 is a deficient number, since it is larger than the sum of its proper divisors (408875217).

919969209 is a wasteful number, since it uses less digits than its factorization.

919969209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102218807 (or 102218804 counting only the distinct ones).

The product of its (nonzero) digits is 708588, while the sum is 54.

The square root of 919969209 is about 30330.9941973553. The cubic root of 919969209 is about 972.5779757418.

The spelling of 919969209 in words is "nine hundred nineteen million, nine hundred sixty-nine thousand, two hundred nine".