684121650 has 48 divisors (see below), whose sum is σ = 1796429664. Its totient is φ = 171700480.

The previous prime is 684121643. The next prime is 684121651. The reversal of 684121650 is 56121486.

684121650 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (684121651) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 131592 + ... + 136691.

It is an arithmetic number, because the mean of its divisors is an integer number (37425618).

Almost surely, 2^684121650 is an apocalyptic number.

684121650 is an abundant number, since it is smaller than the sum of its proper divisors (1112308014).

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

684121650 is a wasteful number, since it uses less digits than its factorization.

684121650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268315 (or 268310 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 684121650 is about 26155.7192598483. The cubic root of 684121650 is about 881.1390424155.

The spelling of 684121650 in words is "six hundred eighty-four million, one hundred twenty-one thousand, six hundred fifty".