51659790 has 128 divisors (see below), whose sum is σ = 154828800. Its totient is φ = 10741248.

The previous prime is 51659761. The next prime is 51659801. The reversal of 51659790 is 9795615.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 346636 + ... + 346784.

It is an arithmetic number, because the mean of its divisors is an integer number (1209600).

Almost surely, 2^51659790 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51659790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77414400).

51659790 is an abundant number, since it is smaller than the sum of its proper divisors (103169010).

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

51659790 is a wasteful number, since it uses less digits than its factorization.

51659790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306.

The product of its (nonzero) digits is 85050, while the sum is 42.

The square root of 51659790 is about 7187.4745216940. The cubic root of 51659790 is about 372.4353355313.

It can be divided in two parts, 516 and 59790, that added together give a palindrome (60306).

The spelling of 51659790 in words is "fifty-one million, six hundred fifty-nine thousand, seven hundred ninety".