51345730405621 has 4 divisors (see below), whose sum is σ = 51345748151244. Its totient is φ = 51345712660000.

The previous prime is 51345730405609. The next prime is 51345730405633. The reversal of 51345730405621 is 12650403754315.

51345730405621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (51345730405609) and next prime (51345730405633).

It can be written as a sum of positive squares in 2 ways, for example, as 40678386517521 + 10667343888100 = 6377961^2 + 3266090^2 .

It is a cyclic number.

It is not a de Polignac number, because 51345730405621 - 2¹¹ = 51345730403573 is a prime.

It is a super-2 number, since 2×51345730405621² (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 (51345730405661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3412630 + ... + 10692871.

It is an arithmetic number, because the mean of its divisors is an integer number (12836437037811).

Almost surely, 2^{51345730405621} is an apocalyptic number.

It is an amenable number.

51345730405621 is a deficient number, since it is larger than the sum of its proper divisors (17745623).

51345730405621 is a wasteful number, since it uses less digits than its factorization.

51345730405621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17745622.

The product of its (nonzero) digits is 1512000, while the sum is 46.

The spelling of 51345730405621 in words is "fifty-one trillion, three hundred forty-five billion, seven hundred thirty million, four hundred five thousand, six hundred twenty-one".