1363681021 has 2 divisors, whose sum is σ = 1363681022. Its totient is φ = 1363681020.

The previous prime is 1363681013. The next prime is 1363681057. The reversal of 1363681021 is 1201863631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1013467225 + 350213796 = 31835^2 + 18714^2 .

It is a cyclic number.

It is not a de Polignac number, because 1363681021 - 2³ = 1363681013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1363681001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 681840510 + 681840511.

It is an arithmetic number, because the mean of its divisors is an integer number (681840511).

Almost surely, 2^1363681021 is an apocalyptic number.

It is an amenable number.

1363681021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1363681021 is an equidigital number, since it uses as much as digits as its factorization.

1363681021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 1363681021 is about 36928.0519524115. The cubic root of 1363681021 is about 1108.9303390208.

The spelling of 1363681021 in words is "one billion, three hundred sixty-three million, six hundred eighty-one thousand, twenty-one".