51221237760 has 1040 divisors, whose sum is σ = 229493734272. Its totient is φ = 10616832000.

The previous prime is 51221237747. The next prime is 51221237819. The reversal of 51221237760 is 6773212215.

51221237760 is a `hidden beast` number, since 5 + 1 + 221 + 2 + 377 + 60 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 127733560 + ... + 127733960.

Almost surely, 2^51221237760 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 51221237760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114746867136).

51221237760 is an abundant number, since it is smaller than the sum of its proper divisors (178272496512).

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

51221237760 is a wasteful number, since it uses less digits than its factorization.

51221237760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 460 (or 429 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

Adding to 51221237760 its reverse (6773212215), we get a palindrome (57994449975).

The spelling of 51221237760 in words is "fifty-one billion, two hundred twenty-one million, two hundred thirty-seven thousand, seven hundred sixty".