1634321021 has 2 divisors, whose sum is σ = 1634321022. Its totient is φ = 1634321020.

The previous prime is 1634321011. The next prime is 1634321033. The reversal of 1634321021 is 1201234361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1527715396 + 106605625 = 39086^2 + 10325^2 .

It is an emirp because it is prime and its reverse (1201234361) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1634321021 - 2¹⁰ = 1634319997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1634321011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 817160510 + 817160511.

It is an arithmetic number, because the mean of its divisors is an integer number (817160511).

Almost surely, 2^1634321021 is an apocalyptic number.

It is an amenable number.

1634321021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1634321021 is an equidigital number, since it uses as much as digits as its factorization.

1634321021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 1634321021 is about 40426.7364623958. The cubic root of 1634321021 is about 1177.9109405721.

Adding to 1634321021 its reverse (1201234361), we get a palindrome (2835555382).

The spelling of 1634321021 in words is "one billion, six hundred thirty-four million, three hundred twenty-one thousand, twenty-one".