67717561 has 4 divisors (see below), whose sum is σ = 69292432. Its totient is φ = 66142692.

The previous prime is 67717537. The next prime is 67717567. The reversal of 67717561 is 16571776.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67717561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67717567) 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 3 ways as a sum of consecutive naturals, for example, 787371 + ... + 787456.

It is an arithmetic number, because the mean of its divisors is an integer number (17323108).

Almost surely, 2^67717561 is an apocalyptic number.

It is an amenable number.

67717561 is a deficient number, since it is larger than the sum of its proper divisors (1574871).

67717561 is a wasteful number, since it uses less digits than its factorization.

67717561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1574870.

The product of its digits is 61740, while the sum is 40.

The square root of 67717561 is about 8229.0680517298. The cubic root of 67717561 is about 407.5996188381.

The spelling of 67717561 in words is "sixty-seven million, seven hundred seventeen thousand, five hundred sixty-one".