21107946 has 8 divisors (see below), whose sum is σ = 42215904. Its totient is φ = 7035980.

The previous prime is 21107929. The next prime is 21107953. The reversal of 21107946 is 64970112.

It is a happy number.

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

21107946 is an admirable number.

It is a super-5 number, since 5×21107946⁵ (a number of 38 digits) contains 55555 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1758990 + ... + 1759001.

It is an arithmetic number, because the mean of its divisors is an integer number (5276988).

Almost surely, 2^21107946 is an apocalyptic number.

21107946 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21107946 is a wasteful number, since it uses less digits than its factorization.

21107946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3517996.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 21107946 is about 4594.3384725116. The cubic root of 21107946 is about 276.3643319190.

The spelling of 21107946 in words is "twenty-one million, one hundred seven thousand, nine hundred forty-six".