256346989 has 8 divisors (see below), whose sum is σ = 265885848. Its totient is φ = 246945600.

The previous prime is 256346969. The next prime is 256347043. The reversal of 256346989 is 989643652.

It can be written as a sum of positive squares in 4 ways, for example, as 104244100 + 152102889 = 10210^2 + 12333^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256346989 - 2¹⁵ = 256314221 is a prime.

It is a super-2 number, since 2×256346989² = 131427557538732242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256346939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30562 + ... + 38035.

It is an arithmetic number, because the mean of its divisors is an integer number (33235731).

Almost surely, 2^256346989 is an apocalyptic number.

It is an amenable number.

256346989 is a deficient number, since it is larger than the sum of its proper divisors (9538859).

256346989 is a wasteful number, since it uses less digits than its factorization.

256346989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68735.

The product of its digits is 2799360, while the sum is 52.

The square root of 256346989 is about 16010.8397343800. The cubic root of 256346989 is about 635.2471718445.

It can be divided in two parts, 25634 and 6989, that added together give a palindrome (32623).

The spelling of 256346989 in words is "two hundred fifty-six million, three hundred forty-six thousand, nine hundred eighty-nine".