898689251981 has 2 divisors, whose sum is σ = 898689251982. Its totient is φ = 898689251980.

The previous prime is 898689251959. The next prime is 898689251989. The reversal of 898689251981 is 189152986898.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 727864922500 + 170824329481 = 853150^2 + 413309^2 .

It is a cyclic number.

It is not a de Polignac number, because 898689251981 - 2¹⁴ = 898689235597 is a prime.

It is a super-2 number, since 2×898689251981² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 898689251899 and 898689251908.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (898689251989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 449344625990 + 449344625991.

It is an arithmetic number, because the mean of its divisors is an integer number (449344625991).

Almost surely, 2^898689251981 is an apocalyptic number.

It is an amenable number.

898689251981 is a deficient number, since it is larger than the sum of its proper divisors (1).

898689251981 is an equidigital number, since it uses as much as digits as its factorization.

898689251981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 179159040, while the sum is 74.

The spelling of 898689251981 in words is "eight hundred ninety-eight billion, six hundred eighty-nine million, two hundred fifty-one thousand, nine hundred eighty-one".