67252781 has 2 divisors, whose sum is σ = 67252782. Its totient is φ = 67252780.

The previous prime is 67252771. The next prime is 67252793. The reversal of 67252781 is 18725276.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57229225 + 10023556 = 7565^2 + 3166^2 .

It is a cyclic number.

It is not a de Polignac number, because 67252781 - 2¹⁰ = 67251757 is a prime.

It is a super-2 number, since 2×67252781² = 9045873104467922, which contains 22 as substring.

It is a Sophie Germain prime.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67252771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33626390 + 33626391.

It is an arithmetic number, because the mean of its divisors is an integer number (33626391).

Almost surely, 2^67252781 is an apocalyptic number.

67252781 is the 3668-th centered decagonal number.

It is an amenable number.

67252781 is a deficient number, since it is larger than the sum of its proper divisors (1).

67252781 is an equidigital number, since it uses as much as digits as its factorization.

67252781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47040, while the sum is 38.

The square root of 67252781 is about 8200.7792922380. The cubic root of 67252781 is about 406.6649561724.

The spelling of 67252781 in words is "sixty-seven million, two hundred fifty-two thousand, seven hundred eighty-one".