51240019 has 2 divisors, whose sum is σ = 51240020. Its totient is φ = 51240018.

The previous prime is 51240001. The next prime is 51240073. The reversal of 51240019 is 91004215.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51240019 - 2¹⁵ = 51207251 is a prime.

It is a super-2 number, since 2×51240019² = 5251079094240722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51241019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25620009 + 25620010.

It is an arithmetic number, because the mean of its divisors is an integer number (25620010).

Almost surely, 2^51240019 is an apocalyptic number.

51240019 is a deficient number, since it is larger than the sum of its proper divisors (1).

51240019 is an equidigital number, since it uses as much as digits as its factorization.

51240019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 51240019 is about 7158.2133944162. The cubic root of 51240019 is about 371.4238271936.

The spelling of 51240019 in words is "fifty-one million, two hundred forty thousand, nineteen".