21046658 has 4 divisors (see below), whose sum is σ = 31569990. Its totient is φ = 10523328.

The previous prime is 21046639. The next prime is 21046681. The reversal of 21046658 is 85664012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18464209 + 2582449 = 4297^2 + 1607^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5261663 + ... + 5261666.

Almost surely, 2^21046658 is an apocalyptic number.

21046658 is a deficient number, since it is larger than the sum of its proper divisors (10523332).

21046658 is a wasteful number, since it uses less digits than its factorization.

21046658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10523331.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 21046658 is about 4587.6636755543. The cubic root of 21046658 is about 276.0965932999.

The spelling of 21046658 in words is "twenty-one million, forty-six thousand, six hundred fifty-eight".