256036409 has 8 divisors (see below), whose sum is σ = 265777920. Its totient is φ = 246387600.

The previous prime is 256036399. The next prime is 256036421. The reversal of 256036409 is 904630652.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256036409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256036489) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17522 + ... + 28619.

It is an arithmetic number, because the mean of its divisors is an integer number (33222240).

Almost surely, 2^256036409 is an apocalyptic number.

It is an amenable number.

256036409 is a deficient number, since it is larger than the sum of its proper divisors (9741511).

256036409 is a wasteful number, since it uses less digits than its factorization.

256036409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46351.

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 256036409 is about 16001.1377407983. The cubic root of 256036409 is about 634.9905212796.

The spelling of 256036409 in words is "two hundred fifty-six million, thirty-six thousand, four hundred nine".