256400449600 has 63 divisors (see below), whose sum is σ = 630955198717. Its totient is φ = 102552078080.

The previous prime is 256400449567. The next prime is 256400449601. The reversal of 256400449600 is 6944004652.

It is a happy number.

The square root of 256400449600 is 506360.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 92304161856 + 164096287744 = 303816^2 + 405088^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256400449601) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 20248071 + ... + 20260729.

Almost surely, 2^256400449600 is an apocalyptic number.

256400449600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

256400449600 is the 506360-th square number.

It is an amenable number.

256400449600 is an abundant number, since it is smaller than the sum of its proper divisors (374554749117).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256400449600 is an frugal number, since it uses more digits than its factorization.

256400449600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25340 (or 12666 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 40.

The spelling of 256400449600 in words is "two hundred fifty-six billion, four hundred million, four hundred forty-nine thousand, six hundred".