20261431 has 2 divisors, whose sum is σ = 20261432. Its totient is φ = 20261430.

The previous prime is 20261419. The next prime is 20261497. The reversal of 20261431 is 13416202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20261431 - 2⁷ = 20261303 is a prime.

It is a super-2 number, since 2×20261431² = 821051172335522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20261399 and 20261408.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20261231) 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 as a sum of consecutive naturals, namely, 10130715 + 10130716.

It is an arithmetic number, because the mean of its divisors is an integer number (10130716).

Almost surely, 2^20261431 is an apocalyptic number.

20261431 is a deficient number, since it is larger than the sum of its proper divisors (1).

20261431 is an equidigital number, since it uses as much as digits as its factorization.

20261431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 20261431 is about 4501.2699319192. The cubic root of 20261431 is about 272.6193669452.

Adding to 20261431 its reverse (13416202), we get a palindrome (33677633).

The spelling of 20261431 in words is "twenty million, two hundred sixty-one thousand, four hundred thirty-one".