51418979089920 has 640 divisors, whose sum is σ = 203476732905600. Its totient is φ = 12220525707264.

The previous prime is 51418979089883. The next prime is 51418979089939. The reversal of 51418979089920 is 2998097981415.

51418979089920 is a `hidden beast` number, since 51 + 418 + 9 + 79 + 0 + 8 + 9 + 92 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a super-2 number, since 2×51418979089920² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 25071624 + ... + 27044856.

It is an arithmetic number, because the mean of its divisors is an integer number (317932395165).

Almost surely, 2^{51418979089920} 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 51418979089920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101738366452800).

51418979089920 is an abundant number, since it is smaller than the sum of its proper divisors (152057753815680).

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

51418979089920 is a wasteful number, since it uses less digits than its factorization.

51418979089920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1973307 (or 1973285 counting only the distinct ones).

The product of its (nonzero) digits is 117573120, while the sum is 72.

The spelling of 51418979089920 in words is "fifty-one trillion, four hundred eighteen billion, nine hundred seventy-nine million, eighty-nine thousand, nine hundred twenty".