51565174021 has 16 divisors (see below), whose sum is σ = 54396469440. Its totient is φ = 48811150080.

The previous prime is 51565174007. The next prime is 51565174049. The reversal of 51565174021 is 12047156515.

It is a cyclic number.

It is not a de Polignac number, because 51565174021 - 2¹⁹ = 51564649733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51565174091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 347085 + ... + 472861.

It is an arithmetic number, because the mean of its divisors is an integer number (3399779340).

Almost surely, 2^51565174021 is an apocalyptic number.

It is an amenable number.

51565174021 is a deficient number, since it is larger than the sum of its proper divisors (2831295419).

51565174021 is a wasteful number, since it uses less digits than its factorization.

51565174021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126084.

The product of its (nonzero) digits is 42000, while the sum is 37.

The spelling of 51565174021 in words is "fifty-one billion, five hundred sixty-five million, one hundred seventy-four thousand, twenty-one".