21046642 has 16 divisors (see below), whose sum is σ = 33636960. Its totient is φ = 9847872.

The previous prime is 21046639. The next prime is 21046681. The reversal of 21046642 is 24664012.

It is a super-2 number, since 2×21046642² = 885922278952328, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 183 + ... + 6490.

It is an arithmetic number, because the mean of its divisors is an integer number (2102310).

Almost surely, 2^21046642 is an apocalyptic number.

21046642 is a deficient number, since it is larger than the sum of its proper divisors (12590318).

21046642 is a wasteful number, since it uses less digits than its factorization.

21046642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6777.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 21046642 is about 4587.6619317469. The cubic root of 21046642 is about 276.0965233356.

The spelling of 21046642 in words is "twenty-one million, forty-six thousand, six hundred forty-two".