21406674 has 32 divisors (see below), whose sum is σ = 44198784. Its totient is φ = 6907520.

The previous prime is 21406663. The next prime is 21406699. The reversal of 21406674 is 47660412.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42307 + ... + 42809.

It is an arithmetic number, because the mean of its divisors is an integer number (1381212).

Almost surely, 2^21406674 is an apocalyptic number.

21406674 is an abundant number, since it is smaller than the sum of its proper divisors (22792110).

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

21406674 is a wasteful number, since it uses less digits than its factorization.

With its successor (21406675) it forms an eRAP, since the sums of their prime factors are consecutive (722 and 723).

21406674 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722.

The product of its (nonzero) digits is 8064, while the sum is 30.

The square root of 21406674 is about 4626.7347017092. The cubic root of 21406674 is about 277.6619685895.

The spelling of 21406674 in words is "twenty-one million, four hundred six thousand, six hundred seventy-four".