1255555440 has 60 divisors (see below), whose sum is σ = 4216576104. Its totient is φ = 334814592.

The previous prime is 1255555439. The next prime is 1255555501. The reversal of 1255555440 is 445555521.

1255555440 is a `hidden beast` number, since 12 + 5 + 55 + 554 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1255555395 and 1255555404.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 871194 + ... + 872633.

Almost surely, 2^1255555440 is an apocalyptic number.

1255555440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1255555440 is an abundant number, since it is smaller than the sum of its proper divisors (2961020664).

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

1255555440 is a wasteful number, since it uses less digits than its factorization.

1255555440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1743846 (or 1743837 counting only the distinct ones).

The product of its (nonzero) digits is 100000, while the sum is 36.

The square root of 1255555440 is about 35433.8177451993. The cubic root of 1255555440 is about 1078.8108310253.

The spelling of 1255555440 in words is "one billion, two hundred fifty-five million, five hundred fifty-five thousand, four hundred forty".