67661577 has 6 divisors (see below), whose sum is σ = 97733402. Its totient is φ = 45107712.

The previous prime is 67661563. The next prime is 67661579. The reversal of 67661577 is 77516676.

67661577 is a `hidden beast` number, since 6 + 76 + 6 + 1 + 577 = 666.

It can be written as a sum of positive squares in only one way, i.e., 47734281 + 19927296 = 6909^2 + 4464^2 .

It is not a de Polignac number, because 67661577 - 2¹² = 67657481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67661579) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3758968 + ... + 3758985.

Almost surely, 2^67661577 is an apocalyptic number.

It is an amenable number.

67661577 is a deficient number, since it is larger than the sum of its proper divisors (30071825).

67661577 is a wasteful number, since it uses less digits than its factorization.

67661577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7517959 (or 7517956 counting only the distinct ones).

The product of its digits is 370440, while the sum is 45.

The square root of 67661577 is about 8225.6657481325. The cubic root of 67661577 is about 407.4872632048.

The spelling of 67661577 in words is "sixty-seven million, six hundred sixty-one thousand, five hundred seventy-seven".