20499197 has 4 divisors (see below), whose sum is σ = 20660736. Its totient is φ = 20337660.

The previous prime is 20499179. The next prime is 20499209. The reversal of 20499197 is 79199402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 79199402 = 2 ⋅39599701.

It is a cyclic number.

It is not a de Polignac number, because 20499197 - 2⁸ = 20498941 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 (20499397) 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, 80579 + ... + 80832.

It is an arithmetic number, because the mean of its divisors is an integer number (5165184).

Almost surely, 2^20499197 is an apocalyptic number.

It is an amenable number.

20499197 is a deficient number, since it is larger than the sum of its proper divisors (161539).

20499197 is a wasteful number, since it uses less digits than its factorization.

20499197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161538.

The product of its (nonzero) digits is 40824, while the sum is 41.

The square root of 20499197 is about 4527.6038916849. The cubic root of 20499197 is about 273.6816102103.

The spelling of 20499197 in words is "twenty million, four hundred ninety-nine thousand, one hundred ninety-seven".