51689946 has 64 divisors (see below), whose sum is σ = 131383296. Its totient is φ = 13166400.

The previous prime is 51689941. The next prime is 51689969. The reversal of 51689946 is 64998615.

It is a junction number, because it is equal to n+sod(n) for n = 51689895 and 51689904.

It is not an unprimeable number, because it can be changed into a prime (51689941) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23431 + ... + 25541.

It is an arithmetic number, because the mean of its divisors is an integer number (2052864).

Almost surely, 2^51689946 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51689946, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65691648).

51689946 is an abundant number, since it is smaller than the sum of its proper divisors (79693350).

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

51689946 is a wasteful number, since it uses less digits than its factorization.

51689946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2187.

The product of its digits is 466560, while the sum is 48.

The square root of 51689946 is about 7189.5720317693. The cubic root of 51689946 is about 372.5077901769.

The spelling of 51689946 in words is "fifty-one million, six hundred eighty-nine thousand, nine hundred forty-six".