71561601 has 12 divisors (see below), whose sum is σ = 105062100. Its totient is φ = 46925280.

The previous prime is 71561599. The next prime is 71561621. The reversal of 71561601 is 10616517.

71561601 is a `hidden beast` number, since 7 + 1 + 56 + 1 + 601 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7160976 + 64400625 = 2676^2 + 8025^2 .

It is not a de Polignac number, because 71561601 - 2¹ = 71561599 is a prime.

It is not an unprimeable number, because it can be changed into a prime (71561621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64626 + ... + 65723.

It is an arithmetic number, because the mean of its divisors is an integer number (8755175).

Almost surely, 2^71561601 is an apocalyptic number.

It is an amenable number.

71561601 is a deficient number, since it is larger than the sum of its proper divisors (33500499).

71561601 is a wasteful number, since it uses less digits than its factorization.

71561601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130416 (or 130413 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 71561601 is about 8459.4090219116. The cubic root of 71561601 is about 415.1706870337.

The spelling of 71561601 in words is "seventy-one million, five hundred sixty-one thousand, six hundred one".