20421070 has 8 divisors (see below), whose sum is σ = 36757944. Its totient is φ = 8168424.

The previous prime is 20421047. The next prime is 20421073. The reversal of 20421070 is 7012402.

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

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20421073) 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, 1021044 + ... + 1021063.

It is an arithmetic number, because the mean of its divisors is an integer number (4594743).

Almost surely, 2^20421070 is an apocalyptic number.

20421070 is a deficient number, since it is larger than the sum of its proper divisors (16336874).

20421070 is a wasteful number, since it uses less digits than its factorization.

20421070 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2042114.

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 20421070 is about 4518.9678024965. The cubic root of 20421070 is about 273.3334804018. Note that the first 3 decimals are identical.

Adding to 20421070 its reverse (7012402), we get a palindrome (27433472).

The spelling of 20421070 in words is "twenty million, four hundred twenty-one thousand, seventy".