209464947 has 20 divisors (see below), whose sum is σ = 319567776. Its totient is φ = 136669680.

The previous prime is 209464919. The next prime is 209464963. The reversal of 209464947 is 749464902.

It is not a de Polignac number, because 209464947 - 2⁷ = 209464819 is a prime.

It is not an unprimeable number, because it can be changed into a prime (209464247) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 23704 + ... + 31317.

Almost surely, 2^209464947 is an apocalyptic number.

209464947 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

209464947 is a deficient number, since it is larger than the sum of its proper divisors (110102829).

209464947 is an equidigital number, since it uses as much as digits as its factorization.

209464947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55080 (or 55071 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 209464947 is about 14472.9038896830. The cubic root of 209464947 is about 593.8869543061.

Subtracting from 209464947 its sum of digits (45), we obtain a palindrome (209464902).

The spelling of 209464947 in words is "two hundred nine million, four hundred sixty-four thousand, nine hundred forty-seven".