85542421 has 2 divisors, whose sum is σ = 85542422. Its totient is φ = 85542420.

The previous prime is 85542367. The next prime is 85542463. The reversal of 85542421 is 12424558.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75864100 + 9678321 = 8710^2 + 3111^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85542421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85549421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42771210 + 42771211.

It is an arithmetic number, because the mean of its divisors is an integer number (42771211).

Almost surely, 2^85542421 is an apocalyptic number.

It is an amenable number.

85542421 is a deficient number, since it is larger than the sum of its proper divisors (1).

85542421 is an equidigital number, since it uses as much as digits as its factorization.

85542421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12800, while the sum is 31.

The square root of 85542421 is about 9248.9145849662. The cubic root of 85542421 is about 440.6162525366.

Adding to 85542421 its reverse (12424558), we get a palindrome (97966979).

The spelling of 85542421 in words is "eighty-five million, five hundred forty-two thousand, four hundred twenty-one".