51211680 has 192 divisors, whose sum is σ = 180351360. Its totient is φ = 12128256.

The previous prime is 51211679. The next prime is 51211681. The reversal of 51211680 is 8611215.

It is an interprime number because it is at equal distance from previous prime (51211679) and next prime (51211681).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 51211680.

It is not an unprimeable number, because it can be changed into a prime (51211681) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 180819 + ... + 181101.

It is an arithmetic number, because the mean of its divisors is an integer number (939330).

Almost surely, 2^51211680 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 51211680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90175680).

51211680 is an abundant number, since it is smaller than the sum of its proper divisors (129139680).

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

51211680 is a wasteful number, since it uses less digits than its factorization.

51211680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343 (or 335 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 24.

The square root of 51211680 is about 7156.2336462695. The cubic root of 51211680 is about 371.3553408742.

Adding to 51211680 its reverse (8611215), we get a palindrome (59822895).

The spelling of 51211680 in words is "fifty-one million, two hundred eleven thousand, six hundred eighty".