51320020 has 12 divisors (see below), whose sum is σ = 107772084. Its totient is φ = 20528000.

The previous prime is 51319993. The next prime is 51320033. The reversal of 51320020 is 2002315.

It can be written as a sum of positive squares in 2 ways, for example, as 7203856 + 44116164 = 2684^2 + 6642^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1282981 + ... + 1283020.

It is an arithmetic number, because the mean of its divisors is an integer number (8981007).

Almost surely, 2^51320020 is an apocalyptic number.

It is an amenable number.

51320020 is an abundant number, since it is smaller than the sum of its proper divisors (56452064).

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

51320020 is a wasteful number, since it uses less digits than its factorization.

51320020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2566010 (or 2566008 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 51320020 is about 7163.7992713364. The cubic root of 51320020 is about 371.6170279202.

Adding to 51320020 its reverse (2002315), we get a palindrome (53322335).

The spelling of 51320020 in words is "fifty-one million, three hundred twenty thousand, twenty".