51687042 has 16 divisors (see below), whose sum is σ = 112771872. Its totient is φ = 15662720.

The previous prime is 51687023. The next prime is 51687043. The reversal of 51687042 is 24078615.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 51686994 and 51687012.

It is not an unprimeable number, because it can be changed into a prime (51687043) 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 7 ways as a sum of consecutive naturals, for example, 391503 + ... + 391634.

It is an arithmetic number, because the mean of its divisors is an integer number (7048242).

Almost surely, 2^51687042 is an apocalyptic number.

51687042 is an abundant number, since it is smaller than the sum of its proper divisors (61084830).

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

51687042 is a wasteful number, since it uses less digits than its factorization.

51687042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 783153.

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 51687042 is about 7189.3700697627. The cubic root of 51687042 is about 372.5008140757.

The spelling of 51687042 in words is "fifty-one million, six hundred eighty-seven thousand, forty-two".