51209844 has 24 divisors (see below), whose sum is σ = 136559808. Its totient is φ = 14631360.

The previous prime is 51209843. The next prime is 51209863. The reversal of 51209844 is 44890215.

51209844 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51209843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 304737 + ... + 304904.

It is an arithmetic number, because the mean of its divisors is an integer number (5689992).

Almost surely, 2^51209844 is an apocalyptic number.

It is an amenable number.

51209844 is an abundant number, since it is smaller than the sum of its proper divisors (85349964).

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

51209844 is a wasteful number, since it uses less digits than its factorization.

51209844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 609655 (or 609653 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 51209844 is about 7156.1053653506. The cubic root of 51209844 is about 371.3509029768.

The spelling of 51209844 in words is "fifty-one million, two hundred nine thousand, eight hundred forty-four".