1255440 has 40 divisors (see below), whose sum is σ = 3892608. Its totient is φ = 334720.

The previous prime is 1255427. The next prime is 1255451. The reversal of 1255440 is 445521.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×1255440² = 3152259187200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (21) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2376 + ... + 2855.

2^1255440 is an apocalyptic number.

1255440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1255440 is an abundant number, since it is smaller than the sum of its proper divisors (2637168).

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

1255440 is a wasteful number, since it uses less digits than its factorization.

1255440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5247 (or 5241 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 1255440 is about 1120.4641895215. The cubic root of 1255440 is about 107.8777766844.

It can be divided in two parts, 125 and 5440, that added together give a triangular number (5565 = T₁₀₅).

The spelling of 1255440 in words is "one million, two hundred fifty-five thousand, four hundred forty".