51111055550 has 48 divisors (see below), whose sum is σ = 96268338432. Its totient is φ = 20186268000.

The previous prime is 51111055531. The next prime is 51111055559. The reversal of 51111055550 is 5555011115.

It is a happy number.

It is a super-2 number, since 2×51111055550² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51111055559) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11480825 + ... + 11485275.

It is an arithmetic number, because the mean of its divisors is an integer number (2005590384).

Almost surely, 2^51111055550 is an apocalyptic number.

51111055550 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

51111055550 is a deficient number, since it is larger than the sum of its proper divisors (45157282882).

51111055550 is a wasteful number, since it uses less digits than its factorization.

51111055550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7313 (or 7308 counting only the distinct ones).

The product of its (nonzero) digits is 3125, while the sum is 29.

Adding to 51111055550 its reverse (5555011115), we get a palindrome (56666066665).

The spelling of 51111055550 in words is "fifty-one billion, one hundred eleven million, fifty-five thousand, five hundred fifty".