20471431 has 4 divisors (see below), whose sum is σ = 20568664. Its totient is φ = 20374200.

The previous prime is 20471413. The next prime is 20471441. The reversal of 20471431 is 13417402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13417402 = 2 ⋅6708701.

It is a cyclic number.

It is not a de Polignac number, because 20471431 - 2¹³ = 20463239 is a prime.

It is a super-2 number, since 2×20471431² = 838158974375522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20471411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48300 + ... + 48721.

It is an arithmetic number, because the mean of its divisors is an integer number (5142166).

Almost surely, 2^20471431 is an apocalyptic number.

20471431 is a deficient number, since it is larger than the sum of its proper divisors (97233).

20471431 is an equidigital number, since it uses as much as digits as its factorization.

20471431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97232.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 20471431 is about 4524.5365508525. The cubic root of 20471431 is about 273.5579878537.

Adding to 20471431 its reverse (13417402), we get a palindrome (33888833).

It can be divided in two parts, 20471 and 431, that added together give a palindrome (20902).

The spelling of 20471431 in words is "twenty million, four hundred seventy-one thousand, four hundred thirty-one".