51115550 has 48 divisors (see below), whose sum is σ = 97962480. Its totient is φ = 19837440.

The previous prime is 51115543. The next prime is 51115577. The reversal of 51115550 is 5551115.

It is a happy number.

It is a super-2 number, since 2×51115550² = 5225598903605000, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 452294 + ... + 452406.

It is an arithmetic number, because the mean of its divisors is an integer number (2040885).

Almost surely, 2^51115550 is an apocalyptic number.

51115550 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

51115550 is a deficient number, since it is larger than the sum of its proper divisors (46846930).

51115550 is a wasteful number, since it uses less digits than its factorization.

51115550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 625, while the sum is 23.

The square root of 51115550 is about 7149.5139694947. The cubic root of 51115550 is about 371.1228369555.

Adding to 51115550 its reverse (5551115), we get a palindrome (56666665).

It can be divided in two parts, 511 and 15550, that added together give a palindrome (16061).

The spelling of 51115550 in words is "fifty-one million, one hundred fifteen thousand, five hundred fifty".