51818020380 has 288 divisors, whose sum is σ = 188172230400. Its totient is φ = 11803688064.

The previous prime is 51818020291. The next prime is 51818020391. The reversal of 51818020380 is 8302081815.

51818020380 is a `hidden beast` number, since 5 + 181 + 80 + 20 + 380 = 666.

It is a super-2 number, since 2×51818020380² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 8120031 + ... + 8126409.

It is an arithmetic number, because the mean of its divisors is an integer number (653375800).

Almost surely, 2^51818020380 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 51818020380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94086115200).

51818020380 is an abundant number, since it is smaller than the sum of its proper divisors (136354210020).

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

51818020380 is a wasteful number, since it uses less digits than its factorization.

51818020380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6718 (or 6703 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 36.

The spelling of 51818020380 in words is "fifty-one billion, eight hundred eighteen million, twenty thousand, three hundred eighty".