51311205 has 64 divisors (see below), whose sum is σ = 100742400. Its totient is φ = 24572160.

The previous prime is 51311171. The next prime is 51311207. The reversal of 51311205 is 50211315.

It is not a de Polignac number, because 51311205 - 2²⁰ = 50262629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51311207) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 161707 + ... + 162023.

It is an arithmetic number, because the mean of its divisors is an integer number (1574100).

Almost surely, 2^51311205 is an apocalyptic number.

51311205 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

51311205 is a deficient number, since it is larger than the sum of its proper divisors (49431195).

51311205 is a wasteful number, since it uses less digits than its factorization.

51311205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 451 (or 445 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

The square root of 51311205 is about 7163.1839987536. The cubic root of 51311205 is about 371.5957497284.

It can be divided in two parts, 5131 and 1205, that added together give a palindrome (6336).

The spelling of 51311205 in words is "fifty-one million, three hundred eleven thousand, two hundred five".