21046081 has 16 divisors (see below), whose sum is σ = 25784064. Its totient is φ = 16784064.

The previous prime is 21046073. The next prime is 21046111. The reversal of 21046081 is 18064012.

It is a cyclic number.

It is not a de Polignac number, because 21046081 - 2³ = 21046073 is a prime.

It is a super-2 number, since 2×21046081² = 885875050917122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21046001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4191 + ... + 7723.

It is an arithmetic number, because the mean of its divisors is an integer number (1611504).

Almost surely, 2^21046081 is an apocalyptic number.

It is an amenable number.

21046081 is a deficient number, since it is larger than the sum of its proper divisors (4737983).

21046081 is a wasteful number, since it uses less digits than its factorization.

21046081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3600.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 21046081 is about 4587.6007890835. The cubic root of 21046081 is about 276.0940701885.

The spelling of 21046081 in words is "twenty-one million, forty-six thousand, eighty-one".