51521908 has 24 divisors (see below), whose sum is σ = 92964872. Its totient is φ = 24966144.

The previous prime is 51521903. The next prime is 51521933. The reversal of 51521908 is 80912515.

It can be written as a sum of positive squares in 4 ways, for example, as 26501904 + 25020004 = 5148^2 + 5002^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51521908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51521903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49360 + ... + 50392.

Almost surely, 2^51521908 is an apocalyptic number.

It is an amenable number.

51521908 is a deficient number, since it is larger than the sum of its proper divisors (41442964).

51521908 is a wasteful number, since it uses less digits than its factorization.

51521908 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1411 (or 1409 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 31.

The square root of 51521908 is about 7177.8762875937. The cubic root of 51521908 is about 372.1036921407.

The spelling of 51521908 in words is "fifty-one million, five hundred twenty-one thousand, nine hundred eight".