67561261 has 2 divisors, whose sum is σ = 67561262. Its totient is φ = 67561260.

The previous prime is 67561243. The next prime is 67561267. The reversal of 67561261 is 16216576.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51408900 + 16152361 = 7170^2 + 4019^2 .

It is a cyclic number.

It is not a de Polignac number, because 67561261 - 2⁷ = 67561133 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67561267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33780630 + 33780631.

It is an arithmetic number, because the mean of its divisors is an integer number (33780631).

Almost surely, 2^67561261 is an apocalyptic number.

It is an amenable number.

67561261 is a deficient number, since it is larger than the sum of its proper divisors (1).

67561261 is an equidigital number, since it uses as much as digits as its factorization.

67561261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15120, while the sum is 34.

The square root of 67561261 is about 8219.5657427871. The cubic root of 67561261 is about 407.2857814944.

The spelling of 67561261 in words is "sixty-seven million, five hundred sixty-one thousand, two hundred sixty-one".