1284011881 has 4 divisors (see below), whose sum is σ = 1295374932. Its totient is φ = 1272648832.

The previous prime is 1284011873. The next prime is 1284011891. The reversal of 1284011881 is 1881104821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1881104821 = 3041 ⋅618581.

It can be written as a sum of positive squares in 2 ways, for example, as 64256256 + 1219755625 = 8016^2 + 34925^2 .

It is a cyclic number.

It is not a de Polignac number, because 1284011881 - 2³ = 1284011873 is a prime.

It is a super-2 number, since 2×1284011881² = 3297373021098316322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1284011831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5681356 + ... + 5681581.

It is an arithmetic number, because the mean of its divisors is an integer number (323843733).

Almost surely, 2^1284011881 is an apocalyptic number.

It is an amenable number.

1284011881 is a deficient number, since it is larger than the sum of its proper divisors (11363051).

1284011881 is a wasteful number, since it uses less digits than its factorization.

1284011881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11363050.

The product of its (nonzero) digits is 4096, while the sum is 34.

The square root of 1284011881 is about 35833.1115171429. Note that the first 3 decimals coincide. The cubic root of 1284011881 is about 1086.9002302704.

It can be divided in two parts, 128 and 4011881, that added together give a square (4012009 = 2003²).

The spelling of 1284011881 in words is "one billion, two hundred eighty-four million, eleven thousand, eight hundred eighty-one".