51387241040 has 20 divisors (see below), whose sum is σ = 119475335604. Its totient is φ = 20554896384.

The previous prime is 51387241001. The next prime is 51387241091. The reversal of 51387241040 is 4014278315.

It can be written as a sum of positive squares in 2 ways, for example, as 29994083344 + 21393157696 = 173188^2 + 146264^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321170177 + ... + 321170336.

Almost surely, 2^51387241040 is an apocalyptic number.

It is an amenable number.

51387241040 is an abundant number, since it is smaller than the sum of its proper divisors (68088094564).

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

51387241040 is a wasteful number, since it uses less digits than its factorization.

51387241040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642340526 (or 642340520 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 35.

The spelling of 51387241040 in words is "fifty-one billion, three hundred eighty-seven million, two hundred forty-one thousand, forty".