51513943 has 4 divisors (see below), whose sum is σ = 55476568. Its totient is φ = 47551320.

The previous prime is 51513929. The next prime is 51513949. The reversal of 51513943 is 34931515.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51513943 - 2²⁵ = 17959511 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 (51513949) 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 3 ways as a sum of consecutive naturals, for example, 1981293 + ... + 1981318.

It is an arithmetic number, because the mean of its divisors is an integer number (13869142).

Almost surely, 2^51513943 is an apocalyptic number.

51513943 is a deficient number, since it is larger than the sum of its proper divisors (3962625).

51513943 is a wasteful number, since it uses less digits than its factorization.

51513943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3962624.

The product of its digits is 8100, while the sum is 31.

The square root of 51513943 is about 7177.3214363020. The cubic root of 51513943 is about 372.0845160997.

The spelling of 51513943 in words is "fifty-one million, five hundred thirteen thousand, nine hundred forty-three".