51211517 has 24 divisors (see below), whose sum is σ = 63721440. Its totient is φ = 40914720.

The previous prime is 51211507. The next prime is 51211541. The reversal of 51211517 is 71511215.

It is not a de Polignac number, because 51211517 - 2¹⁰ = 51210493 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 51211492 and 51211501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51211507) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61967 + ... + 62787.

It is an arithmetic number, because the mean of its divisors is an integer number (2655060).

Almost surely, 2^51211517 is an apocalyptic number.

It is an amenable number.

51211517 is a deficient number, since it is larger than the sum of its proper divisors (12509923).

51211517 is a wasteful number, since it uses less digits than its factorization.

51211517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 921 (or 914 counting only the distinct ones).

The product of its digits is 350, while the sum is 23.

The square root of 51211517 is about 7156.2222575881. Note that the first 4 decimals coincide. The cubic root of 51211517 is about 371.3549468822.

The spelling of 51211517 in words is "fifty-one million, two hundred eleven thousand, five hundred seventeen".