681404506 has 16 divisors (see below), whose sum is σ = 1111482216. Its totient is φ = 311993856.

The previous prime is 681404483. The next prime is 681404513. The reversal of 681404506 is 605404186.

It can be written as a sum of positive squares in 4 ways, for example, as 680740281 + 664225 = 26091^2 + 815^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269571 + ... + 272086.

Almost surely, 2^681404506 is an apocalyptic number.

681404506 is a deficient number, since it is larger than the sum of its proper divisors (430077710).

681404506 is a wasteful number, since it uses less digits than its factorization.

681404506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541713.

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 681404506 is about 26103.7259026370. The cubic root of 681404506 is about 879.9709468714.

The spelling of 681404506 in words is "six hundred eighty-one million, four hundred four thousand, five hundred six".