256467780 has 72 divisors (see below), whose sum is σ = 823723992. Its totient is φ = 64367616.

The previous prime is 256467707. The next prime is 256467787. The reversal of 256467780 is 87764652.

256467780 is a `hidden beast` number, since 2 + 564 + 6 + 7 + 7 + 80 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 114190596 + 142277184 = 10686^2 + 11928^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (256467787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38847 + ... + 44966.

It is an arithmetic number, because the mean of its divisors is an integer number (11440611).

Almost surely, 2^256467780 is an apocalyptic number.

256467780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256467780 is an abundant number, since it is smaller than the sum of its proper divisors (567256212).

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

256467780 is a wasteful number, since it uses less digits than its factorization.

256467780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83845 (or 83840 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 45.

The square root of 256467780 is about 16014.6114532948. The cubic root of 256467780 is about 635.3469325796.

The spelling of 256467780 in words is "two hundred fifty-six million, four hundred sixty-seven thousand, seven hundred eighty".