51516420 has 48 divisors (see below), whose sum is σ = 148904448. Its totient is φ = 13294080.

The previous prime is 51516419. The next prime is 51516431. The reversal of 51516420 is 2461515.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11989 + ... + 15708.

It is an arithmetic number, because the mean of its divisors is an integer number (3102176).

Almost surely, 2^51516420 is an apocalyptic number.

It is an amenable number.

51516420 is an abundant number, since it is smaller than the sum of its proper divisors (97388028).

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

51516420 is a wasteful number, since it uses less digits than its factorization.

51516420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27740 (or 27738 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 51516420 is about 7177.4939916380. The cubic root of 51516420 is about 372.0904797834.

Adding to 51516420 its reverse (2461515), we get a palindrome (53977935).

The spelling of 51516420 in words is "fifty-one million, five hundred sixteen thousand, four hundred twenty".