51257220551 has 16 divisors (see below), whose sum is σ = 52716696480. Its totient is φ = 49808056320.

The previous prime is 51257220541. The next prime is 51257220577. The reversal of 51257220551 is 15502275215.

It is a cyclic number.

It is not a de Polignac number, because 51257220551 - 2¹⁰ = 51257219527 is a prime.

It is a super-2 number, since 2×51257220551² (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 (51257220541) 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 15 ways as a sum of consecutive naturals, for example, 20044565 + ... + 20047121.

It is an arithmetic number, because the mean of its divisors is an integer number (3294793530).

Almost surely, 2^51257220551 is an apocalyptic number.

51257220551 is a deficient number, since it is larger than the sum of its proper divisors (1459475929).

51257220551 is a wasteful number, since it uses less digits than its factorization.

51257220551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4354.

The product of its (nonzero) digits is 35000, while the sum is 35.

Adding to 51257220551 its reverse (15502275215), we get a palindrome (66759495766).

The spelling of 51257220551 in words is "fifty-one billion, two hundred fifty-seven million, two hundred twenty thousand, five hundred fifty-one".