51986380 has 48 divisors (see below), whose sum is σ = 113541120. Its totient is φ = 19972800.

The previous prime is 51986377. The next prime is 51986381. The reversal of 51986380 is 8368915.

It is a happy number.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (51986381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118201 + ... + 118639.

It is an arithmetic number, because the mean of its divisors is an integer number (2365440).

Almost surely, 2^51986380 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 51986380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56770560).

51986380 is an abundant number, since it is smaller than the sum of its proper divisors (61554740).

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

51986380 is a wasteful number, since it uses less digits than its factorization.

51986380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670 (or 668 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 51986380 is about 7210.1581119973. The cubic root of 51986380 is about 373.2185251426.

The spelling of 51986380 in words is "fifty-one million, nine hundred eighty-six thousand, three hundred eighty".