51250021004 has 144 divisors (see below), whose sum is σ = 117193386240. Its totient is φ = 19415531520.

The previous prime is 51250021003. The next prime is 51250021007. The reversal of 51250021004 is 40012005215.

It is not an unprimeable number, because it can be changed into a prime (51250021003) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7658492 + ... + 7665180.

It is an arithmetic number, because the mean of its divisors is an integer number (813842960).

Almost surely, 2^51250021004 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 51250021004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58596693120).

51250021004 is an abundant number, since it is smaller than the sum of its proper divisors (65943365236).

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

51250021004 is a wasteful number, since it uses less digits than its factorization.

51250021004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6848 (or 6839 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

Adding to 51250021004 its reverse (40012005215), we get a palindrome (91262026219).

The spelling of 51250021004 in words is "fifty-one billion, two hundred fifty million, twenty-one thousand, four".