51782640 has 160 divisors (see below), whose sum is σ = 197654016. Its totient is φ = 10920960.

The previous prime is 51782609. The next prime is 51782641. The reversal of 51782640 is 4628715.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51782641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20655 + ... + 23025.

Almost surely, 2^51782640 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 51782640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98827008).

51782640 is an abundant number, since it is smaller than the sum of its proper divisors (145871376).

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

51782640 is a wasteful number, since it uses less digits than its factorization.

51782640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2407 (or 2401 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 51782640 is about 7196.0155641855. The cubic root of 51782640 is about 372.7303261517.

The spelling of 51782640 in words is "fifty-one million, seven hundred eighty-two thousand, six hundred forty".