51390290789 has 4 divisors (see below), whose sum is σ = 51398758956. Its totient is φ = 51381822624.

The previous prime is 51390290767. The next prime is 51390290813. The reversal of 51390290789 is 98709209315.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98709209315 = 5 ⋅19741841863.

It can be written as a sum of positive squares in 2 ways, for example, as 42640185025 + 8750105764 = 206495^2 + 93542^2 .

It is a cyclic number.

It is not a de Polignac number, because 51390290789 - 2⁸ = 51390290533 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 51390290789.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51390290719) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4224974 + ... + 4237119.

It is an arithmetic number, because the mean of its divisors is an integer number (12849689739).

Almost surely, 2^51390290789 is an apocalyptic number.

It is an amenable number.

51390290789 is a deficient number, since it is larger than the sum of its proper divisors (8468167).

51390290789 is an equidigital number, since it uses as much as digits as its factorization.

51390290789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8468166.

The product of its (nonzero) digits is 1224720, while the sum is 53.

The spelling of 51390290789 in words is "fifty-one billion, three hundred ninety million, two hundred ninety thousand, seven hundred eighty-nine".