1281998026 has 8 divisors (see below), whose sum is σ = 1959280164. Its totient is φ = 628904640.

The previous prime is 1281997987. The next prime is 1281998027. The reversal of 1281998026 is 6208991821.

It is a Cunningham number, because it is equal to 35805²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 1281998025 + 1 = 35805^2 + 1^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (1281998027) 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, 6047055 + ... + 6047266.

Almost surely, 2^1281998026 is an apocalyptic number.

1281998026 is a deficient number, since it is larger than the sum of its proper divisors (677282138).

1281998026 is a wasteful number, since it uses less digits than its factorization.

1281998026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12094376.

The product of its (nonzero) digits is 124416, while the sum is 46.

The square root of 1281998026 is about 35805.0000139645. Note that the first 4 decimals coincide. The cubic root of 1281998026 is about 1086.3316984586.

The spelling of 1281998026 in words is "one billion, two hundred eighty-one million, nine hundred ninety-eight thousand, twenty-six".