398898926561 has 4 divisors (see below), whose sum is σ = 404363295492. Its totient is φ = 393434557632.

The previous prime is 398898926537. The next prime is 398898926603. The reversal of 398898926561 is 165629898893.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 307071139600 + 91827786961 = 554140^2 + 303031^2 .

It is a cyclic number.

It is not a de Polignac number, because 398898926561 - 2⁶ = 398898926497 is a prime.

It is a super-2 number, since 2×398898926561² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (398898926521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2732184356 + ... + 2732184501.

It is an arithmetic number, because the mean of its divisors is an integer number (101090823873).

Almost surely, 2^398898926561 is an apocalyptic number.

It is an amenable number.

398898926561 is a deficient number, since it is larger than the sum of its proper divisors (5464368931).

398898926561 is an equidigital number, since it uses as much as digits as its factorization.

398898926561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5464368930.

The product of its digits is 403107840, while the sum is 74.

The spelling of 398898926561 in words is "three hundred ninety-eight billion, eight hundred ninety-eight million, nine hundred twenty-six thousand, five hundred sixty-one".