51451930 has 16 divisors (see below), whose sum is σ = 93151944. Its totient is φ = 20461120.

The previous prime is 51451927. The next prime is 51451931. The reversal of 51451930 is 3915415.

It is a Cunningham number, because it is equal to 7173²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 51451929 + 1 = 7173^2 + 1^2 .

It is a super-2 number, since 2×51451930² = 5294602201449800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51451931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13141 + ... + 16600.

Almost surely, 2^51451930 is an apocalyptic number.

51451930 is a deficient number, since it is larger than the sum of its proper divisors (41700014).

51451930 is a wasteful number, since it uses less digits than its factorization.

51451930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29921.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 51451930 is about 7173.0000697058. Note that the first 4 decimals coincide. The cubic root of 51451930 is about 371.9351497930.

The spelling of 51451930 in words is "fifty-one million, four hundred fifty-one thousand, nine hundred thirty".