1255840816 has 10 divisors (see below), whose sum is σ = 2433191612. Its totient is φ = 627920400.

The previous prime is 1255840769. The next prime is 1255840849. The reversal of 1255840816 is 6180485521.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39245010 + ... + 39245041.

Almost surely, 2^1255840816 is an apocalyptic number.

1255840816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1255840816 is a deficient number, since it is larger than the sum of its proper divisors (1177350796).

1255840816 is an equidigital number, since it uses as much as digits as its factorization.

1255840816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78490059 (or 78490053 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 40.

The square root of 1255840816 is about 35437.8444039702. The cubic root of 1255840816 is about 1078.8925593684.

The spelling of 1255840816 in words is "one billion, two hundred fifty-five million, eight hundred forty thousand, eight hundred sixteen".