51449680 has 20 divisors (see below), whose sum is σ = 119620692. Its totient is φ = 20579840.

The previous prime is 51449669. The next prime is 51449687. The reversal of 51449680 is 8694415.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 31629376 + 19820304 = 5624^2 + 4452^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51449687) 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, 321481 + ... + 321640.

Almost surely, 2^51449680 is an apocalyptic number.

It is an amenable number.

51449680 is an abundant number, since it is smaller than the sum of its proper divisors (68171012).

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

51449680 is a wasteful number, since it uses less digits than its factorization.

51449680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 643134 (or 643128 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 51449680 is about 7172.8432298497. The cubic root of 51449680 is about 371.9297281222.

The spelling of 51449680 in words is "fifty-one million, four hundred forty-nine thousand, six hundred eighty".