68640469 has 2 divisors, whose sum is σ = 68640470. Its totient is φ = 68640468.

The previous prime is 68640443. The next prime is 68640491. The reversal of 68640469 is 96404686.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42732369 + 25908100 = 6537^2 + 5090^2 .

It is a cyclic number.

It is not a de Polignac number, because 68640469 - 2⁹ = 68639957 is a prime.

It is a super-2 number, since 2×68640469² = 9423027969079922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68640409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34320234 + 34320235.

It is an arithmetic number, because the mean of its divisors is an integer number (34320235).

Almost surely, 2^68640469 is an apocalyptic number.

It is an amenable number.

68640469 is a deficient number, since it is larger than the sum of its proper divisors (1).

68640469 is an equidigital number, since it uses as much as digits as its factorization.

68640469 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 248832, while the sum is 43.

The square root of 68640469 is about 8284.9543752516. The cubic root of 68640469 is about 409.4429655351.

The spelling of 68640469 in words is "sixty-eight million, six hundred forty thousand, four hundred sixty-nine".