21070673 has 8 divisors (see below), whose sum is σ = 22767528. Its totient is φ = 19384704.

The previous prime is 21070657. The next prime is 21070703. The reversal of 21070673 is 37607012.

It can be written as a sum of positive squares in 4 ways, for example, as 3489424 + 17581249 = 1868^2 + 4193^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21070673 - 2⁴ = 21070657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21070603) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1565 + ... + 6677.

It is an arithmetic number, because the mean of its divisors is an integer number (2845941).

Almost surely, 2^21070673 is an apocalyptic number.

It is an amenable number.

21070673 is a deficient number, since it is larger than the sum of its proper divisors (1696855).

21070673 is a wasteful number, since it uses less digits than its factorization.

21070673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5443.

The product of its (nonzero) digits is 1764, while the sum is 26.

The square root of 21070673 is about 4590.2802746673. The cubic root of 21070673 is about 276.2015654594.

Adding to 21070673 its reverse (37607012), we get a palindrome (58677685).

The spelling of 21070673 in words is "twenty-one million, seventy thousand, six hundred seventy-three".