398038649881 has 2 divisors, whose sum is σ = 398038649882. Its totient is φ = 398038649880.

The previous prime is 398038649843. The next prime is 398038650007. The reversal of 398038649881 is 188946830893.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 396029817481 + 2008832400 = 629309^2 + 44820^2 .

It is a cyclic number.

It is not a de Polignac number, because 398038649881 - 2¹¹ = 398038647833 is a prime.

It is a super-2 number, since 2×398038649881² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (398038649081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199019324940 + 199019324941.

It is an arithmetic number, because the mean of its divisors is an integer number (199019324941).

Almost surely, 2^398038649881 is an apocalyptic number.

It is an amenable number.

398038649881 is a deficient number, since it is larger than the sum of its proper divisors (1).

398038649881 is an equidigital number, since it uses as much as digits as its factorization.

398038649881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 71663616, while the sum is 67.

The spelling of 398038649881 in words is "three hundred ninety-eight billion, thirty-eight million, six hundred forty-nine thousand, eight hundred eighty-one".