51378964 has 144 divisors (see below), whose sum is σ = 129040128. Its totient is φ = 17335296.

The previous prime is 51378961. The next prime is 51378967. The reversal of 51378964 is 46987315.

It is an interprime number because it is at equal distance from previous prime (51378961) and next prime (51378967).

Its product of digits (181440) is a multiple of the sum of its prime divisors (81).

It is a self number, because there is not a number n which added to its sum of digits gives 51378964.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51378961) 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, 2233857 + ... + 2233879.

It is an arithmetic number, because the mean of its divisors is an integer number (896112).

Almost surely, 2^51378964 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 51378964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64520064).

51378964 is an abundant number, since it is smaller than the sum of its proper divisors (77661164).

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

51378964 is a wasteful number, since it uses less digits than its factorization.

51378964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 81 counting only the distinct ones).

The product of its digits is 181440, while the sum is 43.

The square root of 51378964 is about 7167.9121088362. The cubic root of 51378964 is about 371.7592480077.

The spelling of 51378964 in words is "fifty-one million, three hundred seventy-eight thousand, nine hundred sixty-four".