51217740 has 108 divisors (see below), whose sum is σ = 180756576. Its totient is φ = 11704896.

The previous prime is 51217739. The next prime is 51217763. The reversal of 51217740 is 4771215.

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 in 35 ways as a sum of consecutive naturals, for example, 5917 + ... + 11723.

It is an arithmetic number, because the mean of its divisors is an integer number (1673672).

Almost surely, 2^51217740 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51217740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90378288).

51217740 is an abundant number, since it is smaller than the sum of its proper divisors (129538836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51217740 is a wasteful number, since it uses less digits than its factorization.

51217740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5836 (or 5824 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 27.

The square root of 51217740 is about 7156.6570408257. The cubic root of 51217740 is about 371.3699880837.

Adding to 51217740 its reverse (4771215), we get a palindrome (55988955).

The spelling of 51217740 in words is "fifty-one million, two hundred seventeen thousand, seven hundred forty".