51864019 has 2 divisors, whose sum is σ = 51864020. Its totient is φ = 51864018.

The previous prime is 51864017. The next prime is 51864041. The reversal of 51864019 is 91046815.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51864019 - 2¹ = 51864017 is a prime.

It is a super-2 number, since 2×51864019² = 5379752933664722, which contains 22 as substring.

Together with 51864017, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (51864013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25932009 + 25932010.

It is an arithmetic number, because the mean of its divisors is an integer number (25932010).

Almost surely, 2^51864019 is an apocalyptic number.

51864019 is a deficient number, since it is larger than the sum of its proper divisors (1).

51864019 is an equidigital number, since it uses as much as digits as its factorization.

51864019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 51864019 is about 7201.6677929491. The cubic root of 51864019 is about 372.9254787191.

The spelling of 51864019 in words is "fifty-one million, eight hundred sixty-four thousand, nineteen".