1287362381 has 2 divisors, whose sum is σ = 1287362382. Its totient is φ = 1287362380.

The previous prime is 1287362357. The next prime is 1287362393. The reversal of 1287362381 is 1832637821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1218638281 + 68724100 = 34909^2 + 8290^2 .

It is a cyclic number.

It is not a de Polignac number, because 1287362381 - 2⁶ = 1287362317 is a prime.

It is a super-2 number, since 2×1287362381² = 3314603800027978322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1287362311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 643681190 + 643681191.

It is an arithmetic number, because the mean of its divisors is an integer number (643681191).

Almost surely, 2^1287362381 is an apocalyptic number.

It is an amenable number.

1287362381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1287362381 is an equidigital number, since it uses as much as digits as its factorization.

1287362381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 41.

The square root of 1287362381 is about 35879.8325107573. The cubic root of 1287362381 is about 1087.8447948144.

The spelling of 1287362381 in words is "one billion, two hundred eighty-seven million, three hundred sixty-two thousand, three hundred eighty-one".