51210390 has 96 divisors (see below), whose sum is σ = 156017664. Its totient is φ = 10637760.

The previous prime is 51210359. The next prime is 51210391. The reversal of 51210390 is 9301215.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51210391) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14587 + ... + 17753.

It is an arithmetic number, because the mean of its divisors is an integer number (1625184).

Almost surely, 2^51210390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51210390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78008832).

51210390 is an abundant number, since it is smaller than the sum of its proper divisors (104807274).

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

51210390 is a wasteful number, since it uses less digits than its factorization.

51210390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3202 (or 3195 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 21.

The square root of 51210390 is about 7156.1435144916. The cubic root of 51210390 is about 371.3522227547.

The spelling of 51210390 in words is "fifty-one million, two hundred ten thousand, three hundred ninety".