51818558969 has 12 divisors (see below), whose sum is σ = 53685809580. Its totient is φ = 50014198080.

The previous prime is 51818558951. The next prime is 51818558977. The reversal of 51818558969 is 96985581815.

It can be written as a sum of positive squares in 6 ways, for example, as 17118320569 + 34700238400 = 130837^2 + 186280^2 .

It is not a de Polignac number, because 51818558969 - 2¹² = 51818554873 is a prime.

It is a super-2 number, since 2×51818558969² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51818558269) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2841059 + ... + 2859239.

It is an arithmetic number, because the mean of its divisors is an integer number (4473817465).

Almost surely, 2^51818558969 is an apocalyptic number.

It is an amenable number.

51818558969 is a deficient number, since it is larger than the sum of its proper divisors (1867250611).

51818558969 is a wasteful number, since it uses less digits than its factorization.

51818558969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21628 (or 21599 counting only the distinct ones).

The product of its digits is 31104000, while the sum is 65.

The spelling of 51818558969 in words is "fifty-one billion, eight hundred eighteen million, five hundred fifty-eight thousand, nine hundred sixty-nine".