67011561 has 6 divisors (see below), whose sum is σ = 96794490. Its totient is φ = 44674368.

The previous prime is 67011523. The next prime is 67011601. The reversal of 67011561 is 16511076.

It can be written as a sum of positive squares in only one way, i.e., 50851161 + 16160400 = 7131^2 + 4020^2 .

It is a de Polignac number, because none of the positive numbers 2^k-67011561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (67011521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3722856 + ... + 3722873.

It is an arithmetic number, because the mean of its divisors is an integer number (16132415).

Almost surely, 2^67011561 is an apocalyptic number.

It is an amenable number.

67011561 is a deficient number, since it is larger than the sum of its proper divisors (29782929).

67011561 is a wasteful number, since it uses less digits than its factorization.

67011561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7445735 (or 7445732 counting only the distinct ones).

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

The square root of 67011561 is about 8186.0589418841. The cubic root of 67011561 is about 406.1781696750.

The spelling of 67011561 in words is "sixty-seven million, eleven thousand, five hundred sixty-one".