68638757 has 4 divisors (see below), whose sum is σ = 74878656. Its totient is φ = 62398860.

The previous prime is 68638747. The next prime is 68638777. The reversal of 68638757 is 75783686.

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 not a de Polignac number, because 68638757 - 2⁸ = 68638501 is a prime.

It is a super-2 number, since 2×68638757² = 9422557925010098, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68638747) 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, 3119933 + ... + 3119954.

It is an arithmetic number, because the mean of its divisors is an integer number (18719664).

Almost surely, 2^68638757 is an apocalyptic number.

It is an amenable number.

68638757 is a deficient number, since it is larger than the sum of its proper divisors (6239899).

68638757 is a wasteful number, since it uses less digits than its factorization.

68638757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6239898.

The product of its digits is 1693440, while the sum is 50.

The square root of 68638757 is about 8284.8510547867. The cubic root of 68638757 is about 409.4395614588.

Subtracting 68638757 from its reverse (75783686), we obtain a square (7144929 = 2673²).

The spelling of 68638757 in words is "sixty-eight million, six hundred thirty-eight thousand, seven hundred fifty-seven".