1317534821 has 2 divisors, whose sum is σ = 1317534822. Its totient is φ = 1317534820.

The previous prime is 1317534797. The next prime is 1317534839. The reversal of 1317534821 is 1284357131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 857904100 + 459630721 = 29290^2 + 21439^2 .

It is a cyclic number.

It is not a de Polignac number, because 1317534821 - 2²² = 1313340517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1317534871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 658767410 + 658767411.

It is an arithmetic number, because the mean of its divisors is an integer number (658767411).

Almost surely, 2^1317534821 is an apocalyptic number.

It is an amenable number.

1317534821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1317534821 is an equidigital number, since it uses as much as digits as its factorization.

1317534821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 35.

The square root of 1317534821 is about 36297.8624852759. The cubic root of 1317534821 is about 1096.2780046387.

The spelling of 1317534821 in words is "one billion, three hundred seventeen million, five hundred thirty-four thousand, eight hundred twenty-one".