1283901821 has 2 divisors, whose sum is σ = 1283901822. Its totient is φ = 1283901820.

The previous prime is 1283901793. The next prime is 1283901893. The reversal of 1283901821 is 1281093821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 860776921 + 423124900 = 29339^2 + 20570^2 .

It is a cyclic number.

It is not a de Polignac number, because 1283901821 - 2³⁰ = 210159997 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1283901121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 641950910 + 641950911.

It is an arithmetic number, because the mean of its divisors is an integer number (641950911).

Almost surely, 2^1283901821 is an apocalyptic number.

It is an amenable number.

1283901821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1283901821 is an equidigital number, since it uses as much as digits as its factorization.

1283901821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912, while the sum is 35.

The square root of 1283901821 is about 35831.5757537957. The cubic root of 1283901821 is about 1086.8691745719.

The spelling of 1283901821 in words is "one billion, two hundred eighty-three million, nine hundred one thousand, eight hundred twenty-one".