51642 has 24 divisors (see below), whose sum is σ = 118560. Its totient is φ = 16200.

The previous prime is 51637. The next prime is 51647. The reversal of 51642 is 24615.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51637) and next prime (51647).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a plaindrome in base 11.

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51647) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 267 + ... + 417.

It is an arithmetic number, because the mean of its divisors is an integer number (4940).

2⁵¹⁶⁴² is an apocalyptic number.

51642 is the 114-th decagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59280).

51642 is an abundant number, since it is smaller than the sum of its proper divisors (66918).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51642 is a wasteful number, since it uses less digits than its factorization.

51642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178 (or 175 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 51642 is about 227.2487623729. The cubic root of 51642 is about 37.2392578968.

The spelling of 51642 in words is "fifty-one thousand, six hundred forty-two".