1281139476 has 12 divisors (see below), whose sum is σ = 2989325472. Its totient is φ = 427046488.

The previous prime is 1281139459. The next prime is 1281139477. The reversal of 1281139476 is 6749311821.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281139477) 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 3 ways as a sum of consecutive naturals, for example, 53380800 + ... + 53380823.

It is an arithmetic number, because the mean of its divisors is an integer number (249110456).

Almost surely, 2^1281139476 is an apocalyptic number.

It is an amenable number.

1281139476 is an abundant number, since it is smaller than the sum of its proper divisors (1708185996).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1281139476 is a wasteful number, since it uses less digits than its factorization.

1281139476 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106761630 (or 106761628 counting only the distinct ones).

The product of its digits is 72576, while the sum is 42.

The square root of 1281139476 is about 35793.0087586948. The cubic root of 1281139476 is about 1086.0891400094.

The spelling of 1281139476 in words is "one billion, two hundred eighty-one million, one hundred thirty-nine thousand, four hundred seventy-six".