51345680 has 20 divisors (see below), whose sum is σ = 119378892. Its totient is φ = 20538240.

The previous prime is 51345643. The next prime is 51345691. The reversal of 51345680 is 8654315.

51345680 = T₂₆₀₉ + T₂₆₁₀ + ... + T₂₆₂₃.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 32126224 + 19219456 = 5668^2 + 4384^2 .

It is a tau number, because it is divible by the number of its divisors (20).

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, 320831 + ... + 320990.

Almost surely, 2^51345680 is an apocalyptic number.

It is an amenable number.

51345680 is an abundant number, since it is smaller than the sum of its proper divisors (68033212).

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

51345680 is a wasteful number, since it uses less digits than its factorization.

51345680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 641834 (or 641828 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 51345680 is about 7165.5899966437. The cubic root of 51345680 is about 371.6789537475.

Adding to 51345680 its reverse (8654315), we get a palindrome (59999995).

It can be divided in two parts, 51345 and 680, that added together give a palindrome (52025).

The spelling of 51345680 in words is "fifty-one million, three hundred forty-five thousand, six hundred eighty".