51491143 has 8 divisors (see below), whose sum is σ = 57232656. Its totient is φ = 45926400.

The previous prime is 51491119. The next prime is 51491149. The reversal of 51491143 is 34119415.

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-51491143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51491149) 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, 43578 + ... + 44743.

It is an arithmetic number, because the mean of its divisors is an integer number (7154082).

Almost surely, 2^51491143 is an apocalyptic number.

51491143 is a gapful number since it is divisible by the number (53) formed by its first and last digit.

51491143 is a deficient number, since it is larger than the sum of its proper divisors (5741513).

51491143 is a wasteful number, since it uses less digits than its factorization.

51491143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88385.

The product of its digits is 2160, while the sum is 28.

The square root of 51491143 is about 7175.7329242385. The cubic root of 51491143 is about 372.0296133014.

It can be divided in two parts, 51 and 491143, that added together give a palindrome (491194).

The spelling of 51491143 in words is "fifty-one million, four hundred ninety-one thousand, one hundred forty-three".