20419257 has 16 divisors (see below), whose sum is σ = 27941760. Its totient is φ = 13258752.

The previous prime is 20419253. The next prime is 20419279. The reversal of 20419257 is 75291402.

It is not a de Polignac number, because 20419257 - 2² = 20419253 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20419253) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26169 + ... + 26937.

It is an arithmetic number, because the mean of its divisors is an integer number (1746360).

Almost surely, 2^20419257 is an apocalyptic number.

It is an amenable number.

20419257 is a deficient number, since it is larger than the sum of its proper divisors (7522503).

20419257 is a wasteful number, since it uses less digits than its factorization.

20419257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992.

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 20419257 is about 4518.7671991374. The cubic root of 20419257 is about 273.3253912360.

The spelling of 20419257 in words is "twenty million, four hundred nineteen thousand, two hundred fifty-seven".