51421500 has 192 divisors, whose sum is σ = 179786880. Its totient is φ = 12614400.

The previous prime is 51421499. The next prime is 51421511. The reversal of 51421500 is 512415.

51421500 is a `hidden beast` number, since 514 + 2 + 150 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 175354 + ... + 175646.

It is an arithmetic number, because the mean of its divisors is an integer number (936390).

Almost surely, 2^51421500 is an apocalyptic number.

51421500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51421500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89893440).

51421500 is an abundant number, since it is smaller than the sum of its proper divisors (128365380).

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

51421500 is a wasteful number, since it uses less digits than its factorization.

51421500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334 (or 316 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 51421500 is about 7170.8786072559. The cubic root of 51421500 is about 371.8618113158.

Adding to 51421500 its reverse (512415), we get a palindrome (51933915).

The spelling of 51421500 in words is "fifty-one million, four hundred twenty-one thousand, five hundred".