63890581 has 2 divisors, whose sum is σ = 63890582. Its totient is φ = 63890580.

The previous prime is 63890537. The next prime is 63890609. The reversal of 63890581 is 18509836.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51710481 + 12180100 = 7191^2 + 3490^2 .

It is a cyclic number.

It is not a de Polignac number, because 63890581 - 2¹⁵ = 63857813 is a prime.

It is a super-2 number, since 2×63890581² = 8164012681035122, which contains 22 as substring.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63890501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31945290 + 31945291.

It is an arithmetic number, because the mean of its divisors is an integer number (31945291).

Almost surely, 2^63890581 is an apocalyptic number.

It is an amenable number.

63890581 is a deficient number, since it is larger than the sum of its proper divisors (1).

63890581 is an equidigital number, since it uses as much as digits as its factorization.

63890581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 63890581 is about 7993.1583870207. The cubic root of 63890581 is about 399.7719137163.

It can be divided in two parts, 638 and 90581, that added together give a palindrome (91219).

The spelling of 63890581 in words is "sixty-three million, eight hundred ninety thousand, five hundred eighty-one".