1256436480 has 144 divisors (see below), whose sum is σ = 4321588320. Its totient is φ = 309264384.

The previous prime is 1256436451. The next prime is 1256436481. The reversal of 1256436480 is 846346521.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (1256436481) 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 15 ways as a sum of consecutive naturals, for example, 37336 + ... + 62504.

It is an arithmetic number, because the mean of its divisors is an integer number (30011030).

Almost surely, 2^1256436480 is an apocalyptic number.

1256436480 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1256436480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2160794160).

1256436480 is an abundant number, since it is smaller than the sum of its proper divisors (3065151840).

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

1256436480 is a wasteful number, since it uses less digits than its factorization.

1256436480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25206 (or 25192 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 39.

The square root of 1256436480 is about 35446.2477562859. The cubic root of 1256436480 is about 1079.0631106752.

The spelling of 1256436480 in words is "one billion, two hundred fifty-six million, four hundred thirty-six thousand, four hundred eighty".