551781865519 has 2 divisors, whose sum is σ = 551781865520. Its totient is φ = 551781865518.

The previous prime is 551781865517. The next prime is 551781865543. The reversal of 551781865519 is 915568187155.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 551781865519 - 2¹ = 551781865517 is a prime.

It is a super-2 number, since 2×551781865519² (a number of 24 digits) contains 22 as substring.

Together with 551781865517, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (551781865511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 275890932759 + 275890932760.

It is an arithmetic number, because the mean of its divisors is an integer number (275890932760).

Almost surely, 2^551781865519 is an apocalyptic number.

551781865519 is a deficient number, since it is larger than the sum of its proper divisors (1).

551781865519 is an equidigital number, since it uses as much as digits as its factorization.

551781865519 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120000, while the sum is 61.

The spelling of 551781865519 in words is "five hundred fifty-one billion, seven hundred eighty-one million, eight hundred sixty-five thousand, five hundred nineteen".