6561738 has 12 divisors (see below), whose sum is σ = 14217138. Its totient is φ = 2187240.

The previous prime is 6561721. The next prime is 6561761. The reversal of 6561738 is 8371656.

6561738 is a `hidden beast` number, since 6 + 5 + 617 + 38 = 666.

6561738 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 6487209 + 74529 = 2547^2 + 273^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 182253 + ... + 182288.

Almost surely, 2^6561738 is an apocalyptic number.

6561738 is an abundant number, since it is smaller than the sum of its proper divisors (7655400).

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

6561738 is a wasteful number, since it uses less digits than its factorization.

6561738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364549 (or 364546 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 6561738 is about 2561.5889600012. The cubic root of 6561738 is about 187.2145630244.

The spelling of 6561738 in words is "six million, five hundred sixty-one thousand, seven hundred thirty-eight".