256621051640469 has 8 divisors (see below), whose sum is σ = 342548900947552. Its totient is φ = 170886951713520.

The previous prime is 256621051640461. The next prime is 256621051640507. The reversal of 256621051640469 is 964046150126652.

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

It is not a de Polignac number, because 256621051640469 - 2³ = 256621051640461 is a prime.

It is a super-2 number, since 2×256621051640469² (a number of 30 digits) 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 (256621051640461) 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, 48437341942 + ... + 48437347239.

It is an arithmetic number, because the mean of its divisors is an integer number (42818612618444).

Almost surely, 2^{256621051640469} is an apocalyptic number.

It is an amenable number.

256621051640469 is a deficient number, since it is larger than the sum of its proper divisors (85927849307083).

256621051640469 is an equidigital number, since it uses as much as digits as its factorization.

256621051640469 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96874690067.

The product of its (nonzero) digits is 18662400, while the sum is 57.

The spelling of 256621051640469 in words is "two hundred fifty-six trillion, six hundred twenty-one billion, fifty-one million, six hundred forty thousand, four hundred sixty-nine".