1268206538 has 4 divisors (see below), whose sum is σ = 1902309810. Its totient is φ = 634103268.

The previous prime is 1268206523. The next prime is 1268206543. The reversal of 1268206538 is 8356028621.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 867125809 + 401080729 = 29447^2 + 20027^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1268206495 and 1268206504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 317051633 + ... + 317051636.

Almost surely, 2^1268206538 is an apocalyptic number.

1268206538 is a deficient number, since it is larger than the sum of its proper divisors (634103272).

1268206538 is an equidigital number, since it uses as much as digits as its factorization.

1268206538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 634103271.

The product of its (nonzero) digits is 138240, while the sum is 41.

The square root of 1268206538 is about 35611.8875938920. The cubic root of 1268206538 is about 1082.4221295282.

The spelling of 1268206538 in words is "one billion, two hundred sixty-eight million, two hundred six thousand, five hundred thirty-eight".