51511521 has 8 divisors (see below), whose sum is σ = 68985504. Its totient is φ = 34189280.

The previous prime is 51511517. The next prime is 51511529. The reversal of 51511521 is 12511515.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51511521 - 2² = 51511517 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51511529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37140 + ... + 38501.

It is an arithmetic number, because the mean of its divisors is an integer number (8623188).

Almost surely, 2^51511521 is an apocalyptic number.

It is an amenable number.

51511521 is a deficient number, since it is larger than the sum of its proper divisors (17473983).

51511521 is a wasteful number, since it uses less digits than its factorization.

51511521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75871.

The product of its digits is 250, while the sum is 21.

The square root of 51511521 is about 7177.1527084214. The cubic root of 51511521 is about 372.0786846506.

The spelling of 51511521 in words is "fifty-one million, five hundred eleven thousand, five hundred twenty-one".