63123581 has 4 divisors (see below), whose sum is σ = 64065792. Its totient is φ = 62181372.

The previous prime is 63123547. The next prime is 63123589. The reversal of 63123581 is 18532136.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-63123581 is a prime.

It is a super-2 number, since 2×63123581² = 7969172956527122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63123589) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 471005 + ... + 471138.

It is an arithmetic number, because the mean of its divisors is an integer number (16016448).

Almost surely, 2^63123581 is an apocalyptic number.

It is an amenable number.

63123581 is a deficient number, since it is larger than the sum of its proper divisors (942211).

63123581 is an equidigital number, since it uses as much as digits as its factorization.

63123581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 942210.

The product of its digits is 4320, while the sum is 29.

The square root of 63123581 is about 7945.0349904831. The cubic root of 63123581 is about 398.1657285614.

The spelling of 63123581 in words is "sixty-three million, one hundred twenty-three thousand, five hundred eighty-one".