51721711 has 4 divisors (see below), whose sum is σ = 51947800. Its totient is φ = 51495624.

The previous prime is 51721697. The next prime is 51721721. The reversal of 51721711 is 11712715.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51721711 - 2⁵ = 51721679 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 (51721721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112701 + ... + 113158.

It is an arithmetic number, because the mean of its divisors is an integer number (12986950).

Almost surely, 2^51721711 is an apocalyptic number.

51721711 is a deficient number, since it is larger than the sum of its proper divisors (226089).

51721711 is a wasteful number, since it uses less digits than its factorization.

51721711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226088.

The product of its digits is 490, while the sum is 25.

The square root of 51721711 is about 7191.7807947684. The cubic root of 51721711 is about 372.5840802348.

The spelling of 51721711 in words is "fifty-one million, seven hundred twenty-one thousand, seven hundred eleven".