21073197 has 8 divisors (see below), whose sum is σ = 28128160. Its totient is φ = 14033520.

The previous prime is 21073193. The next prime is 21073201. The reversal of 21073197 is 79137012.

It is an interprime number because it is at equal distance from previous prime (21073193) and next prime (21073201).

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

It is not a de Polignac number, because 21073197 - 2² = 21073193 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21073193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79 + ... + 6492.

It is an arithmetic number, because the mean of its divisors is an integer number (3516020).

Almost surely, 2^21073197 is an apocalyptic number.

It is an amenable number.

21073197 is a deficient number, since it is larger than the sum of its proper divisors (7054963).

21073197 is a wasteful number, since it uses less digits than its factorization.

21073197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7643.

The product of its (nonzero) digits is 2646, while the sum is 30.

The square root of 21073197 is about 4590.5551951806. Note that the first 3 decimals coincide. The cubic root of 21073197 is about 276.2125935032.

The spelling of 21073197 in words is "twenty-one million, seventy-three thousand, one hundred ninety-seven".