51555501660 has 288 divisors, whose sum is σ = 161070275520. Its totient is φ = 12308275200.

The previous prime is 51555501631. The next prime is 51555501661. The reversal of 51555501660 is 6610555515.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51555501661) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 111833830 + ... + 111834290.

It is an arithmetic number, because the mean of its divisors is an integer number (559271790).

Almost surely, 2^51555501660 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 51555501660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80535137760).

51555501660 is an abundant number, since it is smaller than the sum of its proper divisors (109514773860).

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

51555501660 is a wasteful number, since it uses less digits than its factorization.

51555501660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 809 (or 794 counting only the distinct ones).

The product of its (nonzero) digits is 112500, while the sum is 39.

The spelling of 51555501660 in words is "fifty-one billion, five hundred fifty-five million, five hundred one thousand, six hundred sixty".