989818381 has 2 divisors, whose sum is σ = 989818382. Its totient is φ = 989818380.

The previous prime is 989818369. The next prime is 989818393. The reversal of 989818381 is 183818989.

It is a balanced prime because it is at equal distance from previous prime (989818369) and next prime (989818393).

It can be written as a sum of positive squares in only one way, i.e., 874148356 + 115670025 = 29566^2 + 10755^2 .

It is a cyclic number.

It is not a de Polignac number, because 989818381 - 2⁹ = 989817869 is a prime.

It is a super-2 number, since 2×989818381² = 1959480854730922322, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (989818481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494909190 + 494909191.

It is an arithmetic number, because the mean of its divisors is an integer number (494909191).

Almost surely, 2^989818381 is an apocalyptic number.

It is an amenable number.

989818381 is a deficient number, since it is larger than the sum of its proper divisors (1).

989818381 is an equidigital number, since it uses as much as digits as its factorization.

989818381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 995328, while the sum is 55.

The square root of 989818381 is about 31461.3791973588. The cubic root of 989818381 is about 996.5945430273.

The spelling of 989818381 in words is "nine hundred eighty-nine million, eight hundred eighteen thousand, three hundred eighty-one".