51342281640 has 192 divisors, whose sum is σ = 179976036240. Its totient is φ = 12618547200.

The previous prime is 51342281629. The next prime is 51342281651. The reversal of 51342281640 is 4618224315.

It is a happy number.

51342281640 is a `hidden beast` number, since 5 + 1 + 3 + 4 + 2 + 2 + 8 + 1 + 640 = 666.

It is an interprime number because it is at equal distance from previous prime (51342281629) and next prime (51342281651).

It can be written as a sum of positive squares in 8 ways, for example, as 17264383236 + 34077898404 = 131394^2 + 184602^2 .

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 = 51342281595 and 51342281604.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3141490 + ... + 3157790.

Almost surely, 2^51342281640 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 51342281640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89988018120).

51342281640 is an abundant number, since it is smaller than the sum of its proper divisors (128633754600).

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

51342281640 is a wasteful number, since it uses less digits than its factorization.

51342281640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17004 (or 16997 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 51342281640 in words is "fifty-one billion, three hundred forty-two million, two hundred eighty-one thousand, six hundred forty".