21247046 has 8 divisors (see below), whose sum is σ = 32180304. Its totient is φ = 10520280.

The previous prime is 21247033. The next prime is 21247049. The reversal of 21247046 is 64074212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21247046² = 902873927452232, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21247049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51365 + ... + 51776.

It is an arithmetic number, because the mean of its divisors is an integer number (4022538).

Almost surely, 2^21247046 is an apocalyptic number.

21247046 is a deficient number, since it is larger than the sum of its proper divisors (10933258).

21247046 is a wasteful number, since it uses less digits than its factorization.

21247046 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103246.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 21247046 is about 4609.4518112244. The cubic root of 21247046 is about 276.9700776151.

The spelling of 21247046 in words is "twenty-one million, two hundred forty-seven thousand, forty-six".