205420031 has 2 divisors, whose sum is σ = 205420032. Its totient is φ = 205420030.

The previous prime is 205420003. The next prime is 205420037. The reversal of 205420031 is 130024502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 205420031 - 2²² = 201225727 is a prime.

It is a super-3 number, since 3×205420031³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 205419991 and 205420009.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205420037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102710015 + 102710016.

It is an arithmetic number, because the mean of its divisors is an integer number (102710016).

Almost surely, 2^205420031 is an apocalyptic number.

205420031 is a deficient number, since it is larger than the sum of its proper divisors (1).

205420031 is an equidigital number, since it uses as much as digits as its factorization.

205420031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 205420031 is about 14332.4816762485. The cubic root of 205420031 is about 590.0392878176.

Adding to 205420031 its reverse (130024502), we get a palindrome (335444533).

The spelling of 205420031 in words is "two hundred five million, four hundred twenty thousand, thirty-one".