20247191 has 8 divisors (see below), whose sum is σ = 21083520. Its totient is φ = 19420128.

The previous prime is 20247131. The next prime is 20247193. The reversal of 20247191 is 19174202.

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 20247191 - 2⁶ = 20247127 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20247191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20247193) 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, 2330 + ... + 6776.

It is an arithmetic number, because the mean of its divisors is an integer number (2635440).

Almost surely, 2^20247191 is an apocalyptic number.

20247191 is a deficient number, since it is larger than the sum of its proper divisors (836329).

20247191 is a wasteful number, since it uses less digits than its factorization.

20247191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4633.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 20247191 is about 4499.6878780644. The cubic root of 20247191 is about 272.5554851525. Note that the first 3 decimals are identical.

The spelling of 20247191 in words is "twenty million, two hundred forty-seven thousand, one hundred ninety-one".