51363520231021 has 8 divisors (see below), whose sum is σ = 51588543048120. Its totient is φ = 51138536547072.

The previous prime is 51363520230989. The next prime is 51363520231087. The reversal of 51363520231021 is 12013202536315.

It can be written as a sum of positive squares in 4 ways, for example, as 389432162025 + 50974088068996 = 624045^2 + 7139614^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 51363520231021 - 2⁵ = 51363520230989 is a prime.

It is a super-2 number, since 2×51363520231021² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51363520231091) 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, 7150926 + ... + 12404143.

It is an arithmetic number, because the mean of its divisors is an integer number (6448567881015).

Almost surely, 2^{51363520231021} is an apocalyptic number.

It is an amenable number.

51363520231021 is a deficient number, since it is larger than the sum of its proper divisors (225022817099).

51363520231021 is a wasteful number, since it uses less digits than its factorization.

51363520231021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19566575.

The product of its (nonzero) digits is 32400, while the sum is 34.

Adding to 51363520231021 its reverse (12013202536315), we get a palindrome (63376722767336).

The spelling of 51363520231021 in words is "fifty-one trillion, three hundred sixty-three billion, five hundred twenty million, two hundred thirty-one thousand, twenty-one".