51578921 has 8 divisors (see below), whose sum is σ = 52565760. Its totient is φ = 50595952.

The previous prime is 51578899. The next prime is 51578927. The reversal of 51578921 is 12987515.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51578921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51578927) 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, 50411 + ... + 51423.

It is an arithmetic number, because the mean of its divisors is an integer number (6570720).

Almost surely, 2^51578921 is an apocalyptic number.

It is an amenable number.

51578921 is a deficient number, since it is larger than the sum of its proper divisors (986839).

51578921 is a wasteful number, since it uses less digits than its factorization.

51578921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1935.

The product of its digits is 25200, while the sum is 38.

The square root of 51578921 is about 7181.8466288274. The cubic root of 51578921 is about 372.2408954404.

The spelling of 51578921 in words is "fifty-one million, five hundred seventy-eight thousand, nine hundred twenty-one".