684137207 has 4 divisors (see below), whose sum is σ = 736763160. Its totient is φ = 631511256.

The previous prime is 684137203. The next prime is 684137221. The reversal of 684137207 is 702731486.

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

It is a cyclic number.

It is not a de Polignac number, because 684137207 - 2² = 684137203 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 (684137203) 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 3 ways as a sum of consecutive naturals, for example, 26312957 + ... + 26312982.

It is an arithmetic number, because the mean of its divisors is an integer number (184190790).

Almost surely, 2^684137207 is an apocalyptic number.

684137207 is a deficient number, since it is larger than the sum of its proper divisors (52625953).

684137207 is a wasteful number, since it uses less digits than its factorization.

684137207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52625952.

The product of its (nonzero) digits is 56448, while the sum is 38.

The square root of 684137207 is about 26156.0166500941. The cubic root of 684137207 is about 881.1457214304.

The spelling of 684137207 in words is "six hundred eighty-four million, one hundred thirty-seven thousand, two hundred seven".