51690750 has 64 divisors (see below), whose sum is σ = 132245568. Its totient is φ = 13448000.

The previous prime is 51690721. The next prime is 51690757. The reversal of 51690750 is 5709615.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51690757) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1260730 + ... + 1260770.

It is an arithmetic number, because the mean of its divisors is an integer number (2066337).

Almost surely, 2^51690750 is an apocalyptic number.

51690750 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 51690750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66122784).

51690750 is an abundant number, since it is smaller than the sum of its proper divisors (80554818).

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

51690750 is an frugal number, since it uses more digits than its factorization.

51690750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 9450, while the sum is 33.

The square root of 51690750 is about 7189.6279458676. The cubic root of 51690750 is about 372.5097215306.

The spelling of 51690750 in words is "fifty-one million, six hundred ninety thousand, seven hundred fifty".