51891801 has 8 divisors (see below), whose sum is σ = 74511360. Its totient is φ = 31933392.

The previous prime is 51891787. The next prime is 51891809. The reversal of 51891801 is 10819815.

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

It is not a de Polignac number, because 51891801 - 2²⁵ = 18337369 is a prime.

It is a super-2 number, since 2×51891801² = 5385518022047202, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (51891809) 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, 665241 + ... + 665318.

It is an arithmetic number, because the mean of its divisors is an integer number (9313920).

Almost surely, 2^51891801 is an apocalyptic number.

It is an amenable number.

51891801 is a deficient number, since it is larger than the sum of its proper divisors (22619559).

51891801 is a wasteful number, since it uses less digits than its factorization.

51891801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1330575.

The product of its (nonzero) digits is 2880, while the sum is 33.

The square root of 51891801 is about 7203.5963934690. The cubic root of 51891801 is about 372.9920551655.

The spelling of 51891801 in words is "fifty-one million, eight hundred ninety-one thousand, eight hundred one".