512180021 has 2 divisors, whose sum is σ = 512180022. Its totient is φ = 512180020.

The previous prime is 512179999. The next prime is 512180023. The reversal of 512180021 is 120081215.

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., 489958225 + 22221796 = 22135^2 + 4714^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-512180021 is a prime.

Together with 512180023, 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 = 512179975 and 512180002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (512180023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 256090010 + 256090011.

It is an arithmetic number, because the mean of its divisors is an integer number (256090011).

Almost surely, 2^512180021 is an apocalyptic number.

It is an amenable number.

512180021 is a deficient number, since it is larger than the sum of its proper divisors (1).

512180021 is an equidigital number, since it uses as much as digits as its factorization.

512180021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 160, while the sum is 20.

The square root of 512180021 is about 22631.3945880496. The cubic root of 512180021 is about 800.0937499508.

The spelling of 512180021 in words is "five hundred twelve million, one hundred eighty thousand, twenty-one".