986555021 has 2 divisors, whose sum is σ = 986555022. Its totient is φ = 986555020.

The previous prime is 986554979. The next prime is 986555039. The reversal of 986555021 is 120555689.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 729594121 + 256960900 = 27011^2 + 16030^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-986555021 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 986555021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (986555041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493277510 + 493277511.

It is an arithmetic number, because the mean of its divisors is an integer number (493277511).

Almost surely, 2^986555021 is an apocalyptic number.

It is an amenable number.

986555021 is a deficient number, since it is larger than the sum of its proper divisors (1).

986555021 is an equidigital number, since it uses as much as digits as its factorization.

986555021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108000, while the sum is 41.

The square root of 986555021 is about 31409.4734276142. The cubic root of 986555021 is about 995.4981036762.

The spelling of 986555021 in words is "nine hundred eighty-six million, five hundred fifty-five thousand, twenty-one".