51749280 has 288 divisors, whose sum is σ = 201434688. Its totient is φ = 12545280.

The previous prime is 51749249. The next prime is 51749329. The reversal of 51749280 is 8294715.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4704475 + ... + 4704485.

It is an arithmetic number, because the mean of its divisors is an integer number (699426).

It is a vampire number, since it can be written as 5940 ⋅ 8712 (with its own digits).

Almost surely, 2^51749280 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 51749280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100717344).

51749280 is an abundant number, since it is smaller than the sum of its proper divisors (149685408).

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

51749280 is an equidigital number, since it uses as much as digits as its factorization.

51749280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63 (or 21 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 51749280 is about 7193.6972413356. The cubic root of 51749280 is about 372.6502674369.

The spelling of 51749280 in words is "fifty-one million, seven hundred forty-nine thousand, two hundred eighty".