51242142 has 40 divisors (see below), whose sum is σ = 119591496. Its totient is φ = 14636496.

The previous prime is 51242141. The next prime is 51242167. The reversal of 51242142 is 24124215.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51242141) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 12628 + ... + 16184.

Almost surely, 2^51242142 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51242142, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59795748).

51242142 is an abundant number, since it is smaller than the sum of its proper divisors (68349354).

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

51242142 is an equidigital number, since it uses as much as digits as its factorization.

51242142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3590 (or 3569 counting only the distinct ones).

The product of its digits is 640, while the sum is 21.

The square root of 51242142 is about 7158.3616840727. The cubic root of 51242142 is about 371.4289567902.

Adding to 51242142 its reverse (24124215), we get a palindrome (75366357).

The spelling of 51242142 in words is "fifty-one million, two hundred forty-two thousand, one hundred forty-two".