18949655321 has 2 divisors, whose sum is σ = 18949655322. Its totient is φ = 18949655320.

The previous prime is 18949655303. The next prime is 18949655393. The reversal of 18949655321 is 12355694981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17609290000 + 1340365321 = 132700^2 + 36611^2 .

It is a cyclic number.

It is not a de Polignac number, because 18949655321 - 2¹⁴ = 18949638937 is a prime.

It is a super-2 number, since 2×18949655321² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18948655321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9474827660 + 9474827661.

It is an arithmetic number, because the mean of its divisors is an integer number (9474827661).

Almost surely, 2^18949655321 is an apocalyptic number.

It is an amenable number.

18949655321 is a deficient number, since it is larger than the sum of its proper divisors (1).

18949655321 is an equidigital number, since it uses as much as digits as its factorization.

18949655321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2332800, while the sum is 53.

The spelling of 18949655321 in words is "eighteen billion, nine hundred forty-nine million, six hundred fifty-five thousand, three hundred twenty-one".