1213809356 has 12 divisors (see below), whose sum is σ = 2129466360. Its totient is φ = 605390400.

The previous prime is 1213809343. The next prime is 1213809427. The reversal of 1213809356 is 6539083121.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 376766 + ... + 379973.

It is an arithmetic number, because the mean of its divisors is an integer number (177455530).

Almost surely, 2^1213809356 is an apocalyptic number.

It is an amenable number.

1213809356 is a deficient number, since it is larger than the sum of its proper divisors (915657004).

1213809356 is a wasteful number, since it uses less digits than its factorization.

1213809356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 757144 (or 757142 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 1213809356 is about 34839.7668763728. The cubic root of 1213809356 is about 1066.7193182778.

The spelling of 1213809356 in words is "one billion, two hundred thirteen million, eight hundred nine thousand, three hundred fifty-six".