1228685391 has 6 divisors (see below), whose sum is σ = 1774767800. Its totient is φ = 819123588.

The previous prime is 1228685309. The next prime is 1228685399. The reversal of 1228685391 is 1935868221.

It is not a de Polignac number, because 1228685391 - 2¹¹ = 1228683343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1228685399) 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 in 5 ways as a sum of consecutive naturals, for example, 68260291 + ... + 68260308.

Almost surely, 2^1228685391 is an apocalyptic number.

1228685391 is a deficient number, since it is larger than the sum of its proper divisors (546082409).

1228685391 is a wasteful number, since it uses less digits than its factorization.

1228685391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136520605 (or 136520602 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 1228685391 is about 35052.6089043312. The cubic root of 1228685391 is about 1071.0594191652.

The spelling of 1228685391 in words is "one billion, two hundred twenty-eight million, six hundred eighty-five thousand, three hundred ninety-one".