51387740 has 24 divisors (see below), whose sum is σ = 109952640. Its totient is φ = 20166848.

The previous prime is 51387731. The next prime is 51387751. The reversal of 51387740 is 4778315.

It is a self number, because there is not a number n which added to its sum of digits gives 51387740.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23180 + ... + 25299.

It is an arithmetic number, because the mean of its divisors is an integer number (4581360).

Almost surely, 2^51387740 is an apocalyptic number.

It is an amenable number.

51387740 is an abundant number, since it is smaller than the sum of its proper divisors (58564900).

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

51387740 is a wasteful number, since it uses less digits than its factorization.

51387740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48541 (or 48539 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 35.

The square root of 51387740 is about 7168.5242553820. The cubic root of 51387740 is about 371.7804134366.

The spelling of 51387740 in words is "fifty-one million, three hundred eighty-seven thousand, seven hundred forty".