51323490 has 64 divisors (see below), whose sum is σ = 137491200. Its totient is φ = 13623552.

The previous prime is 51323471. The next prime is 51323501. The reversal of 51323490 is 9432315.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 116691 + ... + 117129.

It is an arithmetic number, because the mean of its divisors is an integer number (2148300).

Almost surely, 2^51323490 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51323490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68745600).

51323490 is an abundant number, since it is smaller than the sum of its proper divisors (86167710).

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

51323490 is a wasteful number, since it uses less digits than its factorization.

51323490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 888 (or 882 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 51323490 is about 7164.0414571665. The cubic root of 51323490 is about 371.6254033522.

The spelling of 51323490 in words is "fifty-one million, three hundred twenty-three thousand, four hundred ninety".