51642668 has 72 divisors (see below), whose sum is σ = 121519440. Its totient is φ = 18923520.

The previous prime is 51642629. The next prime is 51642671. The reversal of 51642668 is 86624615.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35948 + ... + 37356.

It is an arithmetic number, because the mean of its divisors is an integer number (1687770).

Almost surely, 2^51642668 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 51642668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60759720).

51642668 is an abundant number, since it is smaller than the sum of its proper divisors (69876772).

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

51642668 is a wasteful number, since it uses less digits than its factorization.

51642668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1455 (or 1446 counting only the distinct ones).

The product of its digits is 69120, while the sum is 38.

The square root of 51642668 is about 7186.2833231094. The cubic root of 51642668 is about 372.3941846191.

The spelling of 51642668 in words is "fifty-one million, six hundred forty-two thousand, six hundred sixty-eight".