51503400 has 288 divisors, whose sum is σ = 194987520. Its totient is φ = 12096000.

The previous prime is 51503393. The next prime is 51503407. The reversal of 51503400 is 430515.

It is an interprime number because it is at equal distance from previous prime (51503393) and next prime (51503407).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51503407) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 725365 + ... + 725435.

It is an arithmetic number, because the mean of its divisors is an integer number (677040).

Almost surely, 2^51503400 is an apocalyptic number.

51503400 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 51503400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97493760).

51503400 is an abundant number, since it is smaller than the sum of its proper divisors (143484120).

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

51503400 is a wasteful number, since it uses less digits than its factorization.

51503400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 125 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 51503400 is about 7176.5869325188. The cubic root of 51503400 is about 372.0591303855.

Adding to 51503400 its reverse (430515), we get a palindrome (51933915).

The spelling of 51503400 in words is "fifty-one million, five hundred three thousand, four hundred".