684351940 has 12 divisors (see below), whose sum is σ = 1437139116. Its totient is φ = 273740768.

The previous prime is 684351931. The next prime is 684351971. The reversal of 684351940 is 49153486.

It can be written as a sum of positive squares in 2 ways, for example, as 286828096 + 397523844 = 16936^2 + 19938^2 .

It is a junction number, because it is equal to n+sod(n) for n = 684351893 and 684351902.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17108779 + ... + 17108818.

It is an arithmetic number, because the mean of its divisors is an integer number (119761593).

Almost surely, 2^684351940 is an apocalyptic number.

It is an amenable number.

684351940 is an abundant number, since it is smaller than the sum of its proper divisors (752787176).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

684351940 is a wasteful number, since it uses less digits than its factorization.

684351940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34217606 (or 34217604 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 684351940 is about 26160.1211770894. The cubic root of 684351940 is about 881.2379014150.

The spelling of 684351940 in words is "six hundred eighty-four million, three hundred fifty-one thousand, nine hundred forty".