428501581 has 4 divisors (see below), whose sum is σ = 429215164. Its totient is φ = 427788000.

The previous prime is 428501533. The next prime is 428501587. The reversal of 428501581 is 185105824.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 267845956 + 160655625 = 16366^2 + 12675^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-428501581 is a prime.

It is a super-2 number, since 2×428501581² = 367227209838999122, 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 (428501587) 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, 355890 + ... + 357091.

It is an arithmetic number, because the mean of its divisors is an integer number (107303791).

Almost surely, 2^428501581 is an apocalyptic number.

It is an amenable number.

428501581 is a deficient number, since it is larger than the sum of its proper divisors (713583).

428501581 is an equidigital number, since it uses as much as digits as its factorization.

428501581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713582.

The product of its (nonzero) digits is 12800, while the sum is 34.

The square root of 428501581 is about 20700.2797324094. The cubic root of 428501581 is about 753.9064800389.

The spelling of 428501581 in words is "four hundred twenty-eight million, five hundred one thousand, five hundred eighty-one".