51209712 has 160 divisors (see below), whose sum is σ = 164275200. Its totient is φ = 15178752.

The previous prime is 51209677. The next prime is 51209747. The reversal of 51209712 is 21790215.

51209712 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (51209677) and next prime (51209747).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 139353 + ... + 139719.

It is an arithmetic number, because the mean of its divisors is an integer number (1026720).

Almost surely, 2^51209712 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51209712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82137600).

51209712 is an abundant number, since it is smaller than the sum of its proper divisors (113065488).

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

51209712 is a wasteful number, since it uses less digits than its factorization.

51209712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420 (or 408 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 51209712 is about 7156.0961424509. The cubic root of 51209712 is about 371.3505839082.

Adding to 51209712 its reverse (21790215), we get a palindrome (72999927).

The spelling of 51209712 in words is "fifty-one million, two hundred nine thousand, seven hundred twelve".