51515421078 has 32 divisors (see below), whose sum is σ = 113428465920. Its totient is φ = 15467513760.

The previous prime is 51515421077. The next prime is 51515421101. The reversal of 51515421078 is 87012451515.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51515421071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3573250 + ... + 3587637.

It is an arithmetic number, because the mean of its divisors is an integer number (3544639560).

Almost surely, 2^51515421078 is an apocalyptic number.

51515421078 is an abundant number, since it is smaller than the sum of its proper divisors (61913044842).

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

51515421078 is a wasteful number, since it uses less digits than its factorization.

51515421078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7161012.

The product of its (nonzero) digits is 56000, while the sum is 39.

The spelling of 51515421078 in words is "fifty-one billion, five hundred fifteen million, four hundred twenty-one thousand, seventy-eight".