51123643020 has 48 divisors (see below), whose sum is σ = 159051335520. Its totient is φ = 13632971328.

The previous prime is 51123643009. The next prime is 51123643031. The reversal of 51123643020 is 2034632115.

51123643020 is a `hidden beast` number, since 5 + 1 + 12 + 3 + 643 + 0 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (51123643009) and next prime (51123643031).

It is a super-2 number, since 2×51123643020² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 15 ways as a sum of consecutive naturals, for example, 47336167 + ... + 47337246.

It is an arithmetic number, because the mean of its divisors is an integer number (3313569490).

Almost surely, 2^51123643020 is an apocalyptic number.

It is an amenable number.

51123643020 is an abundant number, since it is smaller than the sum of its proper divisors (107927692500).

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

51123643020 is a wasteful number, since it uses less digits than its factorization.

51123643020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94673431 (or 94673423 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The spelling of 51123643020 in words is "fifty-one billion, one hundred twenty-three million, six hundred forty-three thousand, twenty".