51978650 has 24 divisors (see below), whose sum is σ = 97343100. Its totient is φ = 20648960.

The previous prime is 51978629. The next prime is 51978653. The reversal of 51978650 is 5687915.

It can be written as a sum of positive squares in 6 ways, for example, as 3523129 + 48455521 = 1877^2 + 6961^2 .

It is a junction number, because it is equal to n+sod(n) for n = 51978598 and 51978607.

It is not an unprimeable number, because it can be changed into a prime (51978653) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 3962 + ... + 10938.

Almost surely, 2^51978650 is an apocalyptic number.

51978650 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

51978650 is a deficient number, since it is larger than the sum of its proper divisors (45364450).

51978650 is a wasteful number, since it uses less digits than its factorization.

51978650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7138 (or 7133 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 41.

The square root of 51978650 is about 7209.6220427981. The cubic root of 51978650 is about 373.2000259241.

The spelling of 51978650 in words is "fifty-one million, nine hundred seventy-eight thousand, six hundred fifty".