1209985312 has 12 divisors (see below), whose sum is σ = 2382158646. Its totient is φ = 604992640.

The previous prime is 1209985291. The next prime is 1209985313. The reversal of 1209985312 is 2135899021.

It can be written as a sum of positive squares in only one way, i.e., 1208535696 + 1449616 = 34764^2 + 1204^2 .

It is not an unprimeable number, because it can be changed into a prime (1209985313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18905989 + ... + 18906052.

Almost surely, 2^1209985312 is an apocalyptic number.

It is an amenable number.

1209985312 is a deficient number, since it is larger than the sum of its proper divisors (1172173334).

1209985312 is an equidigital number, since it uses as much as digits as its factorization.

1209985312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37812051 (or 37812043 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 1209985312 is about 34784.8431360557. The cubic root of 1209985312 is about 1065.5979250231.

The spelling of 1209985312 in words is "one billion, two hundred nine million, nine hundred eighty-five thousand, three hundred twelve".