51387455638 has 16 divisors (see below), whose sum is σ = 78933960000. Its totient is φ = 25083444672.

The previous prime is 51387455621. The next prime is 51387455659. The reversal of 51387455638 is 83655478315.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1813113 + ... + 1841236.

It is an arithmetic number, because the mean of its divisors is an integer number (4933372500).

Almost surely, 2^51387455638 is an apocalyptic number.

51387455638 is a deficient number, since it is larger than the sum of its proper divisors (27546504362).

51387455638 is a wasteful number, since it uses less digits than its factorization.

51387455638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3654519.

The product of its digits is 12096000, while the sum is 55.

The spelling of 51387455638 in words is "fifty-one billion, three hundred eighty-seven million, four hundred fifty-five thousand, six hundred thirty-eight".