20219149 has 2 divisors, whose sum is σ = 20219150. Its totient is φ = 20219148.

The previous prime is 20219141. The next prime is 20219183. The reversal of 20219149 is 94191202.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20160100 + 59049 = 4490^2 + 243^2 .

It is a cyclic number.

It is not a de Polignac number, because 20219149 - 2³ = 20219141 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20219141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10109574 + 10109575.

It is an arithmetic number, because the mean of its divisors is an integer number (10109575).

Almost surely, 2^20219149 is an apocalyptic number.

It is an amenable number.

20219149 is a deficient number, since it is larger than the sum of its proper divisors (1).

20219149 is an equidigital number, since it uses as much as digits as its factorization.

20219149 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 20219149 is about 4496.5708045131. The cubic root of 20219149 is about 272.4295988488.

The spelling of 20219149 in words is "twenty million, two hundred nineteen thousand, one hundred forty-nine".