51140072640 has 112 divisors (see below), whose sum is σ = 163098528768. Its totient is φ = 13576141824.

The previous prime is 51140072629. The next prime is 51140072663. The reversal of 51140072640 is 4627004115.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 51140072598 and 51140072607.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94639 + ... + 333521.

It is an arithmetic number, because the mean of its divisors is an integer number (1456236864).

Almost surely, 2^51140072640 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 51140072640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81549264384).

51140072640 is an abundant number, since it is smaller than the sum of its proper divisors (111958456128).

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

51140072640 is a wasteful number, since it uses less digits than its factorization.

51140072640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239126 (or 239116 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 30.

Adding to 51140072640 its reverse (4627004115), we get a palindrome (55767076755).

The spelling of 51140072640 in words is "fifty-one billion, one hundred forty million, seventy-two thousand, six hundred forty".