51451940 has 36 divisors (see below), whose sum is σ = 111688668. Its totient is φ = 19909440.

The previous prime is 51451931. The next prime is 51451957. The reversal of 51451940 is 4915415.

It can be written as a sum of positive squares in 2 ways, for example, as 7441984 + 44009956 = 2728^2 + 6634^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17882 + ... + 20558.

It is an arithmetic number, because the mean of its divisors is an integer number (3102463).

Almost surely, 2^51451940 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51451940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55844334).

51451940 is an abundant number, since it is smaller than the sum of its proper divisors (60236728).

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

51451940 is a wasteful number, since it uses less digits than its factorization.

51451940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2748 (or 2715 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 29.

The square root of 51451940 is about 7173.0007667642. Note that the first 3 decimals coincide. The cubic root of 51451940 is about 371.9351738890.

The spelling of 51451940 in words is "fifty-one million, four hundred fifty-one thousand, nine hundred forty".