1668722436 has 72 divisors (see below), whose sum is σ = 4362758400. Its totient is φ = 537243840.

The previous prime is 1668722423. The next prime is 1668722483. The reversal of 1668722436 is 6342278661.

1668722436 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 1668722391 and 1668722400.

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, 734310 + ... + 736578.

Almost surely, 2^1668722436 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 1668722436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2181379200).

1668722436 is an abundant number, since it is smaller than the sum of its proper divisors (2694035964).

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

1668722436 is a wasteful number, since it uses less digits than its factorization.

1668722436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2969 (or 2964 counting only the distinct ones).

The product of its digits is 580608, while the sum is 45.

The square root of 1668722436 is about 40849.9992166463. Note that the first 3 decimals coincide. The cubic root of 1668722436 is about 1186.1183780178.

The spelling of 1668722436 in words is "one billion, six hundred sixty-eight million, seven hundred twenty-two thousand, four hundred thirty-six".