1281981952 has 20 divisors (see below), whose sum is σ = 2561461056. Its totient is φ = 640990720.

The previous prime is 1281981947. The next prime is 1281981971. The reversal of 1281981952 is 2591891821.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 1251424 + ... + 1252447.

Almost surely, 2^1281981952 is an apocalyptic number.

It is an amenable number.

1281981952 is a deficient number, since it is larger than the sum of its proper divisors (1279479104).

1281981952 is an frugal number, since it uses more digits than its factorization.

1281981952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2503889 (or 2503873 counting only the distinct ones).

The product of its digits is 103680, while the sum is 46.

The square root of 1281981952 is about 35804.7755474043. The cubic root of 1281981952 is about 1086.3271582101.

The spelling of 1281981952 in words is "one billion, two hundred eighty-one million, nine hundred eighty-one thousand, nine hundred fifty-two".