20245531 has 2 divisors, whose sum is σ = 20245532. Its totient is φ = 20245530.

The previous prime is 20245529. The next prime is 20245541. The reversal of 20245531 is 13554202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20245531 - 2¹ = 20245529 is a prime.

It is a super-2 number, since 2×20245531² = 819763050943922, which contains 22 as substring.

Together with 20245529, it forms a pair of twin primes.

It is equal to p_1285204 and since 20245531 and 1285204 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20245541) 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, 10122765 + 10122766.

It is an arithmetic number, because the mean of its divisors is an integer number (10122766).

Almost surely, 2^20245531 is an apocalyptic number.

20245531 is a deficient number, since it is larger than the sum of its proper divisors (1).

20245531 is an equidigital number, since it uses as much as digits as its factorization.

20245531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 20245531 is about 4499.5034170450. The cubic root of 20245531 is about 272.5480363090.

Adding to 20245531 its reverse (13554202), we get a palindrome (33799733).

The spelling of 20245531 in words is "twenty million, two hundred forty-five thousand, five hundred thirty-one".