51642831 has 4 divisors (see below), whose sum is σ = 68857112. Its totient is φ = 34428552.

The previous prime is 51642827. The next prime is 51642839. The reversal of 51642831 is 13824615.

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

It is not a de Polignac number, because 51642831 - 2² = 51642827 is a prime.

It is a super-2 number, since 2×51642831² = 5333963987389122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51642839) 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, 8607136 + ... + 8607141.

It is an arithmetic number, because the mean of its divisors is an integer number (17214278).

Almost surely, 2^51642831 is an apocalyptic number.

51642831 is a deficient number, since it is larger than the sum of its proper divisors (17214281).

51642831 is a wasteful number, since it uses less digits than its factorization.

51642831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17214280.

The product of its digits is 5760, while the sum is 30.

The square root of 51642831 is about 7186.2946641506. The cubic root of 51642831 is about 372.3945764152.

The spelling of 51642831 in words is "fifty-one million, six hundred forty-two thousand, eight hundred thirty-one".