51551550540 has 216 divisors, whose sum is σ = 182276574480. Its totient is φ = 11759037696.

The previous prime is 51551550527. The next prime is 51551550553. The reversal of 51551550540 is 4505515515.

51551550540 is a `hidden beast` number, since 5 + 1 + 5 + 51 + 550 + 54 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (51551550527) and next prime (51551550553).

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

It is a junction number, because it is equal to n+sod(n) for n = 51551550495 and 51551550504.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 4483639 + ... + 4495121.

It is an arithmetic number, because the mean of its divisors is an integer number (843873030).

Almost surely, 2^51551550540 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 51551550540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91138287240).

51551550540 is an abundant number, since it is smaller than the sum of its proper divisors (130725023940).

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

51551550540 is a wasteful number, since it uses less digits than its factorization.

51551550540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12021 (or 12009 counting only the distinct ones).

The product of its (nonzero) digits is 62500, while the sum is 36.

The spelling of 51551550540 in words is "fifty-one billion, five hundred fifty-one million, five hundred fifty thousand, five hundred forty".