684797490 has 80 divisors (see below), whose sum is σ = 1983016728. Its totient is φ = 168562944.

The previous prime is 684797479. The next prime is 684797501. The reversal of 684797490 is 94797486.

It is a happy number.

684797490 is a `hidden beast` number, since 6 + 84 + 79 + 7 + 490 = 666.

It is an interprime number because it is at equal distance from previous prime (684797479) and next prime (684797501).

It can be written as a sum of positive squares in 4 ways, for example, as 584817489 + 99980001 = 24183^2 + 9999^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 21987 + ... + 43046.

Almost surely, 2^684797490 is an apocalyptic number.

684797490 is an abundant number, since it is smaller than the sum of its proper divisors (1298219238).

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

684797490 is a wasteful number, since it uses less digits than its factorization.

684797490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65065 (or 65056 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 54.

The square root of 684797490 is about 26168.6356159430. The cubic root of 684797490 is about 881.4291043842.

The spelling of 684797490 in words is "six hundred eighty-four million, seven hundred ninety-seven thousand, four hundred ninety".