213685947 has 12 divisors (see below), whose sum is σ = 309333024. Its totient is φ = 142145520.

The previous prime is 213685943. The next prime is 213685957. The reversal of 213685947 is 749586312.

213685947 is a `hidden beast` number, since 21 + 36 + 8 + 594 + 7 = 666.

It is not a de Polignac number, because 213685947 - 2² = 213685943 is a prime.

It is not an unprimeable number, because it can be changed into a prime (213685943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21603 + ... + 29900.

It is an arithmetic number, because the mean of its divisors is an integer number (25777752).

Almost surely, 2^213685947 is an apocalyptic number.

213685947 is a deficient number, since it is larger than the sum of its proper divisors (95647077).

213685947 is a wasteful number, since it uses less digits than its factorization.

213685947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51970 (or 51967 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 213685947 is about 14618.0007867013. Note that the first 3 decimals coincide. The cubic root of 213685947 is about 597.8496609431.

The spelling of 213685947 in words is "two hundred thirteen million, six hundred eighty-five thousand, nine hundred forty-seven".