20209149 has 8 divisors (see below), whose sum is σ = 29939520. Its totient is φ = 13472748.

The previous prime is 20209139. The next prime is 20209153. The reversal of 20209149 is 94190202.

It is not a de Polignac number, because 20209149 - 2²⁴ = 3431933 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 748487 = 20209149 / (2 + 0 + 2 + 0 + 9 + 1 + 4 + 9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20209109) 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, 374217 + ... + 374270.

It is an arithmetic number, because the mean of its divisors is an integer number (3742440).

Almost surely, 2^20209149 is an apocalyptic number.

It is an amenable number.

20209149 is a deficient number, since it is larger than the sum of its proper divisors (9730371).

20209149 is an equidigital number, since it uses as much as digits as its factorization.

20209149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 748496 (or 748490 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 20209149 is about 4495.4587085191. The cubic root of 20209149 is about 272.3846786391.

The spelling of 20209149 in words is "twenty million, two hundred nine thousand, one hundred forty-nine".