1276984381 has 2 divisors, whose sum is σ = 1276984382. Its totient is φ = 1276984380.

The previous prime is 1276984363. The next prime is 1276984391. The reversal of 1276984381 is 1834896721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 932325156 + 344659225 = 30534^2 + 18565^2 .

It is a cyclic number.

It is not a de Polignac number, because 1276984381 - 2⁷ = 1276984253 is a prime.

It is a super-2 number, since 2×1276984381² = 3261378218635906322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1276984321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 638492190 + 638492191.

It is an arithmetic number, because the mean of its divisors is an integer number (638492191).

Almost surely, 2^1276984381 is an apocalyptic number.

It is an amenable number.

1276984381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1276984381 is an equidigital number, since it uses as much as digits as its factorization.

1276984381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 580608, while the sum is 49.

The square root of 1276984381 is about 35734.9182313322. The cubic root of 1276984381 is about 1084.9137043360.

The spelling of 1276984381 in words is "one billion, two hundred seventy-six million, nine hundred eighty-four thousand, three hundred eighty-one".