51109988 has 6 divisors (see below), whose sum is σ = 89442486. Its totient is φ = 25554992.

The previous prime is 51109969. The next prime is 51109997. The reversal of 51109988 is 88990115.

It can be written as a sum of positive squares in only one way, i.e., 46348864 + 4761124 = 6808^2 + 2182^2 .

It is a super-2 number, since 2×51109988² = 5224461746720288, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6388745 + ... + 6388752.

It is an arithmetic number, because the mean of its divisors is an integer number (14907081).

Almost surely, 2^51109988 is an apocalyptic number.

It is an amenable number.

51109988 is a deficient number, since it is larger than the sum of its proper divisors (38332498).

51109988 is a wasteful number, since it uses less digits than its factorization.

51109988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12777501 (or 12777499 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 41.

The square root of 51109988 is about 7149.1249814226. The cubic root of 51109988 is about 371.1093755588.

The spelling of 51109988 in words is "fifty-one million, one hundred nine thousand, nine hundred eighty-eight".