2121668 has 24 divisors (see below), whose sum is σ = 4032504. Its totient is φ = 972800.

The previous prime is 2121667. The next prime is 2121683. The reversal of 2121668 is 8661212.

It can be written as a sum of positive squares in 4 ways, for example, as 24964 + 2096704 = 158^2 + 1448^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121661) 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, 2408 + ... + 3168.

It is an arithmetic number, because the mean of its divisors is an integer number (168021).

2^2121668 is an apocalyptic number.

It is an amenable number.

2121668 is a deficient number, since it is larger than the sum of its proper divisors (1910836).

2121668 is a wasteful number, since it uses less digits than its factorization.

2121668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823 (or 821 counting only the distinct ones).

The product of its digits is 1152, while the sum is 26.

The square root of 2121668 is about 1456.5946587847. The cubic root of 2121668 is about 128.4968482222.

The spelling of 2121668 in words is "two million, one hundred twenty-one thousand, six hundred sixty-eight".