1283683721 has 2 divisors, whose sum is σ = 1283683722. Its totient is φ = 1283683720.

The previous prime is 1283683679. The next prime is 1283683733. The reversal of 1283683721 is 1273863821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 645414025 + 638269696 = 25405^2 + 25264^2 .

It is a cyclic number.

It is not a de Polignac number, because 1283683721 - 2²² = 1279489417 is a prime.

It is not a weakly prime, because it can be changed into another prime (1283683781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 641841860 + 641841861.

It is an arithmetic number, because the mean of its divisors is an integer number (641841861).

Almost surely, 2^1283683721 is an apocalyptic number.

It is an amenable number.

1283683721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1283683721 is an equidigital number, since it uses as much as digits as its factorization.

1283683721 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 1283683721 is about 35828.5322194477. The cubic root of 1283683721 is about 1086.8076279160.

The spelling of 1283683721 in words is "one billion, two hundred eighty-three million, six hundred eighty-three thousand, seven hundred twenty-one".