51409720 has 32 divisors (see below), whose sum is σ = 115876800. Its totient is φ = 20527488.

The previous prime is 51409697. The next prime is 51409723. The reversal of 51409720 is 2790415.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51409723) 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 7 ways as a sum of consecutive naturals, for example, 40942 + ... + 42178.

It is an arithmetic number, because the mean of its divisors is an integer number (3621150).

Almost surely, 2^51409720 is an apocalyptic number.

It is an amenable number.

51409720 is an abundant number, since it is smaller than the sum of its proper divisors (64467080).

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

51409720 is a wasteful number, since it uses less digits than its factorization.

51409720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2287 (or 2283 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 51409720 is about 7170.0571824777. The cubic root of 51409720 is about 371.8334129047.

The spelling of 51409720 in words is "fifty-one million, four hundred nine thousand, seven hundred twenty".