999872057 has 2 divisors, whose sum is σ = 999872058. Its totient is φ = 999872056.

The previous prime is 999872009. The next prime is 999872059. The reversal of 999872057 is 750278999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 976937536 + 22934521 = 31256^2 + 4789^2 .

It is a cyclic number.

It is not a de Polignac number, because 999872057 - 2¹² = 999867961 is a prime.

It is a super-2 number, since 2×999872057² = 1999488260738822498, which contains 22 as substring.

Together with 999872059, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 999871993 and 999872011.

It is not a weakly prime, because it can be changed into another prime (999872059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499936028 + 499936029.

It is an arithmetic number, because the mean of its divisors is an integer number (499936029).

Almost surely, 2^999872057 is an apocalyptic number.

It is an amenable number.

999872057 is a deficient number, since it is larger than the sum of its proper divisors (1).

999872057 is an equidigital number, since it uses as much as digits as its factorization.

999872057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2857680, while the sum is 56.

The square root of 999872057 is about 31620.7535805205. The cubic root of 999872057 is about 999.9573505144.

The spelling of 999872057 in words is "nine hundred ninety-nine million, eight hundred seventy-two thousand, fifty-seven".