1281990236 has 12 divisors (see below), whose sum is σ = 2291216928. Its totient is φ = 627356832.

The previous prime is 1281990223. The next prime is 1281990253. The reversal of 1281990236 is 6320991821.

It is a junction number, because it is equal to n+sod(n) for n = 1281990193 and 1281990202.

It is a congruent 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, 3409361 + ... + 3409736.

It is an arithmetic number, because the mean of its divisors is an integer number (190934744).

Almost surely, 2^1281990236 is an apocalyptic number.

It is an amenable number.

1281990236 is a deficient number, since it is larger than the sum of its proper divisors (1009226692).

1281990236 is a wasteful number, since it uses less digits than its factorization.

1281990236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6819148 (or 6819146 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 1281990236 is about 35804.8912301099. The cubic root of 1281990236 is about 1086.3294981065.

The spelling of 1281990236 in words is "one billion, two hundred eighty-one million, nine hundred ninety thousand, two hundred thirty-six".