51818340509 has 8 divisors (see below), whose sum is σ = 59086976760. Its totient is φ = 45018648576.

The previous prime is 51818340487. The next prime is 51818340517. The reversal of 51818340509 is 90504381815.

It can be written as a sum of positive squares in 4 ways, for example, as 21132409 + 51797208100 = 4597^2 + 227590^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51818340509 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51818340509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51818340559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117235844 + ... + 117236285.

It is an arithmetic number, because the mean of its divisors is an integer number (7385872095).

Almost surely, 2^51818340509 is an apocalyptic number.

It is an amenable number.

51818340509 is a deficient number, since it is larger than the sum of its proper divisors (7268636251).

51818340509 is a wasteful number, since it uses less digits than its factorization.

51818340509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234472159.

The product of its (nonzero) digits is 172800, while the sum is 44.

The spelling of 51818340509 in words is "fifty-one billion, eight hundred eighteen million, three hundred forty thousand, five hundred nine".