51353786647 has 4 divisors (see below), whose sum is σ = 51392487136. Its totient is φ = 51315086160.

The previous prime is 51353786639. The next prime is 51353786681. The reversal of 51353786647 is 74668735315.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 51353786647 - 2³ = 51353786639 is a prime.

It is a super-2 number, since 2×51353786647² (a number of 22 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 (51353786147) 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, 19348254 + ... + 19350907.

It is an arithmetic number, because the mean of its divisors is an integer number (12848121784).

Almost surely, 2^51353786647 is an apocalyptic number.

51353786647 is a deficient number, since it is larger than the sum of its proper divisors (38700489).

51353786647 is a wasteful number, since it uses less digits than its factorization.

51353786647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38700488.

The product of its digits is 12700800, while the sum is 55.

The spelling of 51353786647 in words is "fifty-one billion, three hundred fifty-three million, seven hundred eighty-six thousand, six hundred forty-seven".