684259957 has 4 divisors (see below), whose sum is σ = 684502816. Its totient is φ = 684017100.

The previous prime is 684259949. The next prime is 684259969. The reversal of 684259957 is 759952486.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 684259957 - 2³ = 684259949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 684259898 and 684259907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684259357) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117153 + ... + 122854.

It is an arithmetic number, because the mean of its divisors is an integer number (171125704).

Almost surely, 2^684259957 is an apocalyptic number.

It is an amenable number.

684259957 is a deficient number, since it is larger than the sum of its proper divisors (242859).

684259957 is a wasteful number, since it uses less digits than its factorization.

684259957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242858.

The product of its digits is 5443200, while the sum is 55.

The square root of 684259957 is about 26158.3630412914. The cubic root of 684259957 is about 881.1984175699.

The spelling of 684259957 in words is "six hundred eighty-four million, two hundred fifty-nine thousand, nine hundred fifty-seven".