51209536 has 56 divisors (see below), whose sum is σ = 117059456. Its totient is φ = 21772800.

The previous prime is 51209467. The next prime is 51209537. The reversal of 51209536 is 63590215.

It is a tau number, because it is divible by the number of its divisors (56).

It is a junction number, because it is equal to n+sod(n) for n = 51209498 and 51209507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51209537) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67270 + ... + 68026.

Almost surely, 2^51209536 is an apocalyptic number.

51209536 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51209536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58529728).

51209536 is an abundant number, since it is smaller than the sum of its proper divisors (65849920).

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

51209536 is a wasteful number, since it uses less digits than its factorization.

51209536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 927 (or 917 counting only the distinct ones).

The product of its (nonzero) digits is 8100, while the sum is 31.

The square root of 51209536 is about 7156.0838452327. The cubic root of 51209536 is about 371.3501584825.

The spelling of 51209536 in words is "fifty-one million, two hundred nine thousand, five hundred thirty-six".